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General Chemistry ICHEM 1111Lab Manual(Updated Spring 2017)San Jacinto Faculty??Revised Spring 2018All text, images, and figures, where not otherwise noted, belong to the Introductory Chemistry Laboratory Manual by San Jacinto Faculty which is licensed under CC-BY 4.0ByDepartment of ChemistrySan Jacinto College Central CampusAdapted forSan Jacinto College South CampusTABLE OF CONTENTS TOC \o "1-3" \h \z \u LAB II. USE OF NUMBERS…………………………………………………………..2LAB III. MEASURING TEMPERATURE, MASS AND VOLUME6LAB IV. GRAPHING DATA…………………………………………………………..9 Part A. Drawing A Graph Of Experimental Data Part B. Graphing With MICROLABLAB V. DENSITY DETERMINATION……………………………………………....15Part A. Determination Of The Density Of A MetalPart B. Determination Of The Density Of A LiquidLAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGES19Part A. Properties Of ElementsPart B. Properties Of CompoundsPart C. Properties Of Homogeneous And Heterogeneous MixturesPart D. Using The Internet For Chemical InformationLAB VII. TYPES OF REACTIONS…………………………………………………...26LAB VIII. PRACTICE EXERCISES…………………………………………………..34LAB IX. SEPARATING MIXTURES43Separation Of A Mixture Containing SiO2, NaCl AND CaCO3LAB X. DETERMINING AN EMPIRICAL FORMULA48Part A. Determining The Empirical Formula Of Zinc ChloridePart B. Determining The Empirical Formula Of Magnesium OxideLAB XI. DOUBLE DISPLACEMENT REACTIONS………………………………..54 Part A Part BLAB XII. SINGLE DISPLACEMENT REACTIONS PAGEREF _Toc133311192 \h 61Part APart BLAB XIII. QUALITATIVE ANALYSIS67LAB XIV. MOLECULAR AND POLYATOMIC ION SHAPES AND BONDING.70LAB XV. BOYLE'S LAW……………………………………………………………...76LAB XVI. MOLAR MASS DETERMINATION……………………………………..79LAB XVII. ACID-BASE REACTIONS……………………………………………....82LAB II. USE OF NUMBERSPART A. SCIENTIFIC NOTATIONPART B. SIGNIFICANT FIGURESThis lab provides practice for writing numbers in scientific notation (also called exponential notation) and significant figures (also called significant digits). In chemistry you frequently use very large numbers and also very small numbers. Scientific notation is used to express these very large or very small numbers. Review Scientific Notation in Chapter 1, pp.18-19, in your textbook.Because calculators sometimes give many nonzero digits in an answer, knowing how many digits to record in an answer is important. Rules for recording the number of significant figures (or meaningful digits) in a calculation or measurement are on pages 19-22 in your text. Complete the problems in Parts A and B.FOR PART A: SCIENTIFIC NOTATION: 6900000 = 6.9 x 106 75247550165To put this number in your calculator:Press 6.9Press EE or EXP (Do not press times 10)Press 6It will probably look like 6.9 E 06020000To put this number in your calculator:Press 6.9Press EE or EXP (Do not press times 10)Press 6It will probably look like 6.9 E 060.000154 = 1.54 x 10-4 742949145415To put this number in your calculator:Press 1.54Press EE or EXPPress +/-Press 4It will probably look like 1.54 E -04 020000To put this number in your calculator:Press 1.54Press EE or EXPPress +/-Press 4It will probably look like 1.54 E -04 LAB II. USE OF NUMBERSNAME: ____________________SECTION:___________Express the following numbers in Scientific Notation, with only one nonzero digit to the left of the decimal place. Do not discard any nonzero digits.1. 3756_____________________2. 0.91______________________3. 265000000______________________4. 0.0415_______________________5. 0.00000029_______________________6. 3364000_______________________7. 183_______________________8. 0.000295_______________________9. 820000______________________10. 0.00000403_______________________Change the following numbers to regular notation.11. 5.71 x 10-4 _______________________12. 8.32 x 105 _______________________13. 4.93 x 10-6_______________________14. 7.64 x 10-2 _______________________15. 2.6 x 103_______________________LAB II. USE OF NUMBERSNAME: ____________________SECTION:___________Perform the following operations using your calculator and write your answer in correct scientific notation.16. (6.5 x 10-4) x (4.7 x 106) = ____________________________17. 7.21 x 10-3 - 9.50 x 10-4 = ____________________________18. 941 / 3.85 x 10-8 ____________________________19. 154.85 + 6.7 x 10-1 = ____________________________20. (87.3/56.3) x 9.41 x 105 =____________________________ LAB II. USE OF NUMBERS NAME: _______________________ SECTION:__________ PART B. SIGNIFICANT FIGURESProvide answers based on the rules for writing significant figures on pages 19-22 in your text.Give the number of significant figures in the following numbers:21. 46.35 __________________________________22. 0.00702__________________________________23. 0.000007020__________________________________24. 1.0 x 105__________________________________25. 9170.0__________________________________26. 6.022 x 1023__________________________________27. 1.5400__________________________________Perform the following calculations and give the answers with the correct number of significant figures and include units on your answers. 28. 4.5792 m + 0.5 m + 2.31 m = ___________________________________29. 5.70 g – 3.8212 g = ___________________________________30. 2.15 cm x 4.6666 cm = ___________________________________31. 58.73 g / 42.6 mL = ___________________________________Round the following numbers to three significant figures.32. 0.50845___________________________________33. 3.046 x 105___________________________________34. 147.86___________________________________35. 26355___________________________________Rounding hints: Round down if the last digit to be dropped is 4 or less.Round up if the last digit to be dropped is 5 or more.Do not round intermediate steps in a multi-step calculation. Round the final answer only.LAB III. MEASURING TEMPERATURE, MASS AND VOLUMEThe purpose of this lab is to introduce you to various measuring techniques that will be used in the lab this semester. Before you begin this lab, be familiar with the metric system; background information is found in Chapter 1 of the text. In Part A of this lab you will measure temperatures using the Celsius scale, oC; in Part B you will measure masses of objects in grams, g, using electronic balances; in Part C you will measure volume of an object by two methods, in cubic centimeters, cm3 and in milliliters, mL, and volumes of liquids in mL. Materials:Equipment: thermometer, beakers, clamps, ring stand, electronic balances, metal objects, metal cylinders, metric rulers, 10-mL and 50-mL graduated cylinders, Beral pipets, hot plates, waxed weighing papers, spatula, small test tube, small beakerReagents: water, ice, sodium chloridePART A. MEASURING TEMPERATURES1. Place a beaker that is half-full of a mixture of ice and tap water on a ring stand, or use room temperature water, if your instructor so directs. Use a clamp to suspend a thermometer into the ice water or room temperature water, so that the thermometer does not touch the bottom or sides of the beaker. After the thermometer has been in the water a few minutes, record the temperature to the nearest 0.1 oC on the Data Sheet. (Estimate the last digit). 2. Place a beaker that is half-full of warm water on a hot plate. Use a ring stand and a clamp to suspend a thermometer into the water so that the thermometer does not touch the bottom or sides of the beaker. Turn on the hot plate and heat the water to about 60oC. Record the temperature of the water to the nearest 0.1oC on the Data Sheet. left358775In all future lab experiments this semester, always obtain temperatures to the nearest 0.1 oC.00In all future lab experiments this semester, always obtain temperatures to the nearest 0.1 oC. PART B. MEASURING MASSES OF OBJECTS3. Obtain two small pieces of metal from the cart. Follow the instructions on using the electronic balance (posted above the balance). Zero the balance and find the mass of the first piece of metal using an electronic balance. Record its mass to the nearest 0.001 gram on the Data Sheet. Find the mass of the second piece of metal. Record its mass to the nearest 0.001 gram on the Data Sheet.4. Place both pieces of metal on the electronic balance and obtain the combined mass of the two pieces of metal to the nearest 0.001 gram and record it on the Data Sheet.5. Obtain one piece of weighing paper and place it on the pan of an electronic balance. Zero/tare the balance, so that it appears that the paper has a mass of 0.000 grams. Using a spatula, place approximately 1.0 gram of sodium chloride, NaCl, on the weighing paper. Record the mass of the NaCl to the nearest 0.001 g on the Data Sheet. Discard the weighing paper and NaCl in the waste 85090356235In all future lab experiments this semester, always obtain masses of objects and/or chemicals to the nearest 0.001 gram. Never place chemicals directly on the balance pan.020000In all future lab experiments this semester, always obtain masses of objects and/or chemicals to the nearest 0.001 gram. Never place chemicals directly on the balance pan. paper basket.PART C. MEASURING VOLUMES 6. Obtain a metric ruler and a solid metal cylinder from the cart. Measure the height and the radius of the cylinder to the nearest 0.01 cm and record on the Data Sheet. The height will probably be 6-7 cm. Obtain the volume of cylinder using the following equation in which r stands for radius, h stands for height and π is a constant. Volume of cylinder = πr2h. Record this volume obtained by direct measurement on the Data Sheet. Be sure to write your answer with the proper units and correct number of significant figures.47625356235In all future lab experiments this semester, always measure lengths to the nearest 0.01 cm.020000In all future lab experiments this semester, always measure lengths to the nearest 0.01 cm. Save this cylinder for Step 8 below.7. Fill a small test tube about half-full of tap water. Pour the water from the test tube into a 10-mL graduated cylinder. When you are eye-level with the bottom of the meniscus, read the volume at the bottom of the meniscus. Record the volume of the water to the nearest 0.01 mL on the Data Sheet. Discard the water.8. Fill a 50-mL graduated cylinder with approximately 30 mL of tap water. Read the exact volume when you are eye-level with the bottom of the meniscus. Record the volume to the nearest 0.1 mL on the Data Sheet. Tilt the graduated cylinder slightly and carefully slip the cylinder from Step 6 into the water in the graduated cylinder. Do not splash out any water. Record the new volume on the Data Sheet to the nearest 0.1 mL. The volume of the cylinder is equal to the difference between the water volumes in the graduated cylinder. Volume of cylinder = Water Volume displaced = V(with metal) –V(without metal) This method of obtaining the volume of an object is called the water displacement method. This method will only work for samples that do not dissolve in water. Compare the volume obtained by this method with the volume by direct measurement in Step 6 above (on line 11 on the Data Sheet).6762754445Beakers should not be used to accurately determine the volume of a liquid.020000Beakers should not be used to accurately determine the volume of a liquid.DATA SHEET: LAB III. Measuring Temperature, Mass, and VolumeNAME(S):_____________________SECTION:___________Use the correct number of digits and include units on your answers.PART A.1. Temperature of ice water mixture: _______ (or room temperature water)2. Temperature of warm water:_______PART B.3. Mass of first object:_______4. Mass of second object:_______ 5. Calculated mass of both objects (add the two):_______6. Mass of both objects obtained from balance:_______7. Difference in Lines 5 and 6:_______8. Mass of NaCl:_______PART C.9. Height of cylinder:_______10. Radius of cylinder:_______11. Volume of cylinder:_______12. Volume of water in test tube:_______13. Volume of water in cylinder:_______14. Volume of water and metal cylinder:_______15. Volume of metal cylinder by water displacement:_______16. Difference in Line 11 and 15:_______ (Remember that 1.0 mL = 1.0 cm3) LAB IV. GRAPHING DATAIn the chemistry laboratory the line graph is the most common graph. The line graph has a horizontal x-axis, or abscissa, and a vertical y-axis, or ordinate. The scale and units on each axis represents the units and range of measurements obtained. The scale on the two axes need not be the same size; however, each subdivision on an axis must have a constant value.A. DRAWING A GRAPH OF EXPERIMENTAL DATAPrepare a graph from the following experimental data:Volume, mL273032363840Temperature, oC2550751001251501. Draw and label the x-axis and the y-axis. Draw axes with a straight edge or ruler. Usually, the independent variable, the variable you control in an experiment, is drawn on the x-axis. The dependent variable, the variable you measure, is plotted on the y-axis. Label each axis with the appropriate unit.2. Select scale for each axis. Select a scale for each axis so that the data points fill, or nearly fill, the entire page of graph paper. The subdivisions of the scale should be easy to read and interpret.3. Place each data point clearly at the appropriate place on the graph.4. Draw the best straight line through the data points. Possibly, the line does not touch all data points. It represents the best averaging of data points.5. Title the graph. The title should communicate the data represented by the graph. An example of a title to use is dependent variable vs. independent variable. 6. Straight-line graphs The line drawn can be described by the general equation: y = mx + b In the equation, m is the slope and b is the intersection of the line along the y-axis at x =0. The slope = QUOTE or QUOTE 7. Answer the questions on the data sheet and attach your graph to the data sheet.LAB IV. A. GRAPHING DATA SHEETNAME____________________________SECTION_________________Use the temperature-volume graph that you have drawn to answer the following questions:1. What is the independent variable?___________________________________2. Give the volume of the sample of gas when the temperature is 60oC__________________mL3. What is the temperature when the volume of gas is 37 mL?_________________________oC4. Calculate the slope of the line you have drawn by using two points that are not data points. Show your calculations here.5. Write the equation of the line: y = _____x + b Attach your graph to this data sheet.B. GRAPHING WITH MICROLABI. PRESSURE AND TEMPERATURE DATA Pressure of a sample of air was measured at various temperatures. The following data was obtained from these measurements:Pressure, mm Hg 712.0751.0788.0824.0865.0Temperature, oC 15.030.045.060.075.0Which property is the independent variable? (Write answer on data sheet).Prepare a graph of this data. User name: your G00 number Password: your SOS password. (--possibly your birth date if you have not changed it) Click on “Start” on the desktop. Select “All Programs”, then MicroLab, and its icon.MicroLabClick on Hand Enter tabClick OKClick on: Add Column Label (lower right of screen) Column AEnter a Label: TemperatureSensor Units: CelsiusClick: OKClick on: Add Column LabelColumn BEnter a Label: PressureSensor Units: mm HgClick: OKLocate Data Sources/ (left side of screen) and look under Sensor for variablesDrag independent variable to X axisDrag dependent variable to Y axisEnter data in columns A and BAfter entering the last data, click in the next column or in the space below and thenClick on Accept Data. (Notice if all data points are on the graph).Click on AnalysisClick on Add Curve FitClick OKChoose Graph Series. Note Domain Minimum and Maximum.Click OKChoose Curve FitLabel: Type appropriate title for graph. (Include your initials)Curve Fit Options: First OrderNotice Correlation Factor (The correlation coefficient is a measure of how “good” the fitof the data is to the curve fit you have chosen. The closer the correlation coefficient is to 1.000, the better the relationship of data and the mathematical function chosen).Click on Print this Graph from the Analysis screenSelect printer: Click on PrintClick on Accept and Save Curve FitWrite answers to the following questions on the Data Sheet.What is the pressure of the sample of air at room temperature, 25oC? B. What is the temperature when the air sample has a pressure of 800 mm Hg?C. Calculate the slope of the line. (Select points that are not data points).What is the y-intercept of the line? Write the equation for the line.Attach the graph to the Data Sheet.II. GRAPHING MASS AND VOLUME DATA The following mass and volume measurements were made of five pieces of the same metal: Mass, g: 0.0 4.8 8.0 16.0 19.0 27.0 Volume, mL:0.0 0.5 0.9 1.8 2.1 3.0 Prepare a graph of the data. Follow steps 1-8 in I.B. In Steps 2 and 3, the column label is Mass in Column A and Volume in Column B. In Step 4, drag Mass to the y axis and Volume to the x axis. The slope of the line is QUOTE = Density of the sample Refer to the table below to find the density and identity of the sample.Metals/AlloysDensity, QUOTE aluminum2.70chromium7.09copper8.92duriron7.00iron7.86lead 11.34nickel8.90stainless steel7.75tin5.75Wood’s metal9.70Zinc7.08 Write answers to the following questions on Data Sheet. The density of the sample is_____________________________(Record on Data Sheet).The identity of the sample is______________________________ (Record on Data Sheet).LAB IV.B. GRAPHING WITH MICROLABDATA SHEETNAME____________________________SECTION_________________I. PRESSURE AND TEMPERATURE DATAA.__________________________________B. 8.A.________________________________ B.________________________________ C.________________________________ D.________________________________ E.________________________________II. MASS AND VOLUME DATA ___________________________________ ___________________________________ Attach graphs of Part I and Part II to this Data Sheet.LAB V. DENSITY DETERMINATIONBefore you begin this lab be familiar with the definition of density and density calculations. Background information is found in Chapter 1 of the text. Density is defined as mass per unit volume or: D = QUOTE The usual units of density are g/mL, although sometimes it is written as g/cm3, but since 1.0 mL equals 1.0 cm3, the numerical value for density does not change. Materials:Equipment: 10-mL graduated cylinders, 5 pieces of the same metal, electronic balancesReagents: water and NaCl solutionPART A. DETERMINATION OF THE DENSITY OF A METAL1. Obtain five samples of the same metal.2. Weigh the first sample to the nearest 0.001 gram and record on Data Sheet 1. 3. Fill a 10-mL graduated cylinder about half full with tap water. Record the volume (at the bottom of the meniscus) to the nearest 0.01 mL on Data Sheet 1. If your metal piece does not fit in the 10-mL graduated cylinder, check with your instructor.4. Carefully slide the sample that you weighed into the water in the graduated cylinder. Record the volume to the nearest 0.01 mL on Data Sheet 1. The difference between the two volumes will be the volume of the sample. This technique for obtaining the volume is the water displacement method. 5. Empty the cylinder, dry the metal sample, and repeat Steps 3 and 4 for this sample. Record on the Data Sheet.6. Repeat Steps 1-5 to obtain mass and volume measurements for the other four samples of the metal.7. Calculate the average volume for each sample and record on your Data Sheet.8. Go to MicroLab and prepare a graph of your data with mass on the y-axis and the average volume on the x-axis. Follow the procedure in Experiment IV, Part II, p. 20. Include an origin (0.000g, 0.00 mL) with your data. The slope of this plot is the density of your metal. Record the density of your sample on the Data Sheet. Check that your graph has an origin and that all of your data points are shown on the graph. Notice the correlation coefficient and how close it is to 1.000. Can you improve the correlation by removing a data point? To remove a point, right click on the point, and select “Remove this point from the Curve Fit set”. The point will be removed from the curve fit and the point will be an “X”. To return the point, right click on the point and select “Add this point to the Curve fit set.” If you remove a point, select curve-fit choice again. 9. Refer to the table on p. 20 to find the metal that has the density closest to the density that you have determined in Step 8. Write the name of the metal on Data Sheet 1.PART B. DETERMINATION OF THE DENSITY OF A LIQUID10. Weigh a clean and dry 10.0-mL graduated cylinder on a previously zeroed electronic balance and record all digits displayed on your Data Sheet. 11. Remove the cylinder from the balance. Using a Beral pipet, add exactly 4.0 mL of tap water to the graduated cylinder. Record the volume on your Data Sheet. 12. Weigh the graduated cylinder with the 4.0 mL of liquid on a previously zeroed electronic balance and record all digits displayed on your Data Sheet.13. Determine the difference between the masses and record the mass of water on your Data Sheet. For Trial 2 repeat steps 10-13 with 7.0 mL of water. For Trial 3 repeat steps 10-13 with 10.0 mL of water.14. Repeat steps 10-13 with a solution of NaCl. Record each density on the Data Sheet using the correct units and number of significant figures.LAB V. DENSITY DETERMINATION - DATA SHEET 1NAME: __________________________SECTION: __________PART A.Sample Number __________1. Mass of metal piece #1, g_______2. Volume of water + metal #1, mL______________3. Initial volume of water, mL______________ 4. Volume of metal piece #1,mL______________Average________5. Mass of metal piece #2, g_______6. Volume of water + metal #2, mL______________7. Initial volume of water, mL______________ 8. Volume of metal piece #2,mL______________Average________9. Mass of metal piece #3, g_______10. Volume of water + metal #3, mL______________11. Initial volume of water, mL______________ 12. Volume of metal piece #3, mL______________Average________13. Mass of metal piece #4, g_______14. Volume of water + metal #4, mL______________15. Initial volume of water, mL______________ 16. Volume of metal piece #4, mL______________Average________17. Mass of metal piece #5 g_______18. Volume of water + metal #5, mL______________19. Initial volume of water, mL______________ 20. Volume of metal piece #5, mL______________Average________21. Density from the slope___________22. Identity of the metal___________ LAB V. DENSITY DETERMINATION - DATA SHEET 2 NAME:_______________________SECTION:__________ PART BWaterTrial 1Trial 2Trial 31. Volume of water, mL _____________________2. Mass of graduated cylinder, g_____________________3. Mass of cylinder and water, g_____________________4. Mass of water, g_____________________5. Density of water, g/mL_____________________6. Average density_______ (Use three significant figures)NaCl solutionTrial 1Trial 2Trial 37. Volume of NaCl solution, mL_____________________8. Mass of graduated cylinder, g_____________________9. Mass of cylinder and solution, g_____________________10. Mass of NaCl solution, g_____________________11. Density of NaCl solution, g/mL_____________________12. Average density_______ (Use three significant figures)LAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGES left880110Proper clothing, shoes and safety glasses should be worn for this lab.020000Proper clothing, shoes and safety glasses should be worn for this lab.Before you begin this lab, you should be familiar with types of matter, pure substances, elements, compounds, heterogeneous mixtures, homogeneous mixtures, chemical and physical properties of substances and chemical and physical changes of substances. Background information is found in Chapter 1 of the text.Materials:Equipment: spatulas, Bunsen burner, striker, 7 small test tubes, glass stirring rods, tongsright710565Check with your instructor and discard all substances in the proper waste container.020000Check with your instructor and discard all substances in the proper waste container.Reagents: Al, C, Fe, Mg, S8, Sn, Zn, deionized water, CuSO4 QUOTE 5H2O, sucrose, NaCl, naphthalene, CaCl2, CaCO3, NH4Cl, beach sand, brass (may be a brass screw), clay or dirt, candle wax, aqueous solution of K2CO3, aqueous solution of Ca(NO3)2Part A. Properties of Elements1. Obtain samples of the elements from the center table. The tray should contain the following samples: Al, C, Fe, Mg, S8, Sn and Zn.2. Place a small sample, approximately 1 gram, of each element in a separate test tube. (A 1-gram sample is about the same amount as a large raisin). No need to weigh each sample. Observe the physical properties of each element and record on Data Sheet 1. To judge the texture and the density of each sample, all samples but the sulfur and carbon can be handled with your hands 3. Add approximately 3 mL of distilled water to each test tube containing an element. Because the small test tubes hold a maximum of 10 mL, fill the test tube approximately 1/3 full. 4. Stir each sample with a glass stirring rod. Between test tubes, rinse the stirring rod with distilled water from your water bottle to keep from cross contaminating.5. Record on Data Sheet 1, if the substance appears to dissolve in the distilled water. For samples that dissolve, also record if any transfer of heat occurs. (Did the test tube feel warm or cool to the touch?)6. After recording the solubility of each, pour the water off the metals (except sulfur and carbon). Retrieve the metals and dry them with a paper towel and keep them for #7. Discard the wet sulfur and wet carbon in the appropriate waste container in the ventilation hood.7. Place a small sample of an element in a deflagration spoon. Place the sample in the Bunsen burner flame directly above the inner blue cone. Heat the sample under the ventilation hood. Record your results on Data Sheet 1. Did it melt? Did it burn? Did it change in color?8. Repeat step 7 with each of the other elements. Obtain fresh samples of sulfur and carbon. Work under the ventilation hood* when using the sulfur and carbon. Clean the spoon between elements. Record your results on Data Sheet 1. Note whether the sample melts, burns, remains unchanged or the substance appears different after heating than before heating.2286009525*Read and follow the posted instructions about proper use of the hoods.020000*Read and follow the posted instructions about proper use of the hoods. 9. Record on Data Sheet 1 whether changes appear to be physical or chemical changes or both.10. Discard all substances in the proper waste container in the ventilation hood.Part B. Properties of Compounds11. Obtain the following samples: C12H22O11 (sucrose or table sugar), NaCl (table salt), CuSO4 QUOTE 5H2O, C10H8 (naphthalene), CaCl2, CaCO3, NH4Cl12. Place a small sample, approximately 1 gram, of each compound in a separate test tube. (No need to weigh each sample). Observe the physical properties of each compound and record on Data Sheet 2. 13. Add approximately 3 mL of deionized water to each test tube containing a compound. Because the small test tubes hold a maximum of 10 mL, fill the test tube approximately 1/3 full. 14. Stir each sample with a glass stirring rod. Between test tubes, rinse the stirring rod with deionized water from your water bottle to keep from cross contaminating. 15. On Data Sheet 2, record if the compound appears to dissolve in the deionized water. If the compound does dissolve, record any transfer of heat.16. After recording the solubility of each, discard all the samples in the solid waste containers in the ventilation hood except for the solutions of sucrose and NaCl. The sucrose and NaCl solutions can be poured down the drain. 17. Obtain fresh samples of each of the compounds. Place a small sample of a compound in a deflagration spoon and hold the spoon in the Bunsen burner flame directly above the inner blue cone. Work under a ventilation hood. Record your results on Data Sheet 2. 18. Repeat step 17 with each of the compounds. Clean the spoon between compounds. Record your results on Data Sheet 2. Note whether the sample melts, burns, remains unchanged or the substance appears different after heating than before heating. Heat CuSO4 QUOTE 5 H2O last because you will use it in step 19 below.19. To the residue left from the CuSO4 QUOTE 5H2O after heating, add a few drops of deionized water. Record your observations on Data Sheet 2.20. Record on Data Sheet 2 whether changes appear to be physical or chemical changes or both when heating each of the compounds.21. Discard all compounds in the proper waste container in the ventilation hood.22. Obtain approximately 1 g of iron power and 1 g of sulfur powder. These are both elements that you described in Part A. Place the two in a small test tube and mix the two carefully with a clean, dry stirring rod. Describe the appearance of the mixture on Data Sheet 2.23. Under a ventilation hood, heat the test tube gently at first with a Bunsen burner while holding the test tube with a test tube holder at an angle and not aimed toward anyone. Then heat the test tube strongly until the test tube contents of Fe and S8 glow red. 24. Cool the test tube under the ventilation hood. When it is cool, wrap it in a paper towel and break the test tube with a hammer. Examine the product and describe its appearance on Data Sheet 2. Is there evidence that a compound has formed? Does it appear different than the mixture of Fe and S8 before heating? Is your observation a chemical or a physical change? Record on Data Sheet 2. Discard in the solid waste container in the ventilation hood. Part C. Properties of Homogeneous and Heterogeneous Mixtures25. Obtain samples of the mixtures: beach sand, brass (may be a brass screw), clay or dirt, candle wax, K2CO3 (aq) and CaCl2 (aq).26. Place a small sample, approximately 1 gram, of each mixture in a separate test tube. Remember that 1 gram is about the same amount as a large raisin. (No need to weigh each sample). Use 1 mL of the liquid mixtures. Observe the physical properties of each mixture and record on Data Sheet 3. Also, record if each mixture is homogeneous or heterogeneous.27. Pour the K2CO3 solution from the small test tube into the test tube containing the CaCl2 solution. Record your observations on Data Sheet 3. Does this appear to be a chemical or a physical change? Discard in the appropriate waste container on the center table. 28. Return all solid substances to the sample cart or the sample table.Part D. Using the Internet for Chemical Information29. Before lab or before you turn in your lab report, use the Internet to obtain information about Ag, an element; CaCO3, a compound; yellow brass, a mixture. Record the information on Data Sheet 4. LAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGESDATA SHEET 1NAMES:__________________ SECTION:_________ELEMENTPhysical PropertiesSolubility inWater Results of Heating Physical or Chemical ChangeNo ChangeAlCFeMgS8SnZnLAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGESDATA SHEET 2NAMES:__________________ SECTION:_________COMPOUNDPhysical PropertiesSolubility in Water (Include any change in temp.)Results of Heating Solid With BurnerPhysical ChangesChemical ChangesSucrose,C12H22O11NaClCuSO4 QUOTE 5H2O(Include after adding water to hot CuSO4)Naphthalene, C10H8CaCl2CaCO3NH4Cl8Fe + S8 8FeS XLAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGESDATA SHEET 3NAMES:__________________ SECTION:_________MIXTUREPhysical Properties(General Description)Homogeneous or Heterogeneous MixtureBeach SandBrassClay or DirtCandle WaxK2CO3(aq)CaCl2(aq)Observation when K2CO3(aq) and CaCl2(aq) are mixed: ______________________________________________________________________________________________________Is this combination of K2CO3(aq) and CaCl2(aq) a physical or chemical change?__________________________________________________ LAB VI. CHEMICAL AND PHYSICAL PROPERTIES AND CHANGESDATA SHEET 4*NAMES:__________________ SECTION:_________SUBSTANCEMM or At. Mass*(If appropriate.)Density*Boiling Point Temp.*Melting Point Temp.*Solubility in Water at ~O0C*HazardsAgCaCO3Yellow Brass*Include units where appropriate.INTERNET SOURCES: Ag:_____________________________________________________________________CaCO3:_________________________________________________________________Yellow Brass:____________________________________________________________LAB VII. TYPES OF REACTIONSBefore you begin this lab be familiar with the types of reactions found in Chapter 4 of the text. The four major types are: combination (also called composition), decomposition, single displacement (called displacement in the text), double displacement. Double displacement includes both neutralization reactions and precipitation reactions. Oxidation-reduction (redox) reactions include many of the other types of reactions. Combination Reactions: two or more reactants one productDecomposition Reactions: one reactant two or more productsDouble Displacement Reactions: switching of ions to form new compoundsPrecipitation Reactions: an insoluble product formsM1X1 + M2X2 M1X2 + M2X1Neutralization Reactions: Acid + Base Salt + H2O HX + MOH MX + H2OSingle Displacement Reactions: free element displaces another element in a compound M1 + M2X M1X + M2 X1 + MX2 MX1 + X2Oxidation-Reduction (redox) Reactions: Includes any reaction that involves change in oxidation numberAll single displacement reactionsSome combination reactions (especially when a free element is a reactant)Some decomposition reactions (especially when a free element is a product)No double displacement reactionsFor each reaction in this experiment, you will write a balanced molecular equation. For reactions that occur in solution, you will also write the ionic equation and the net ionic equation. Refer to pp. 123-124 and pp.130-131 in the text.Evidence that a chemical reaction occurs may include: a color change, the formation of a gas, the formation of an insoluble product.Wear appropriate clothing, shoes and safety glasses.Materials:Equipment: Bunsen burner, striker or matches, small test tubes, spatulas, crucible with lid, clay triangle, ring, ring stand, test tube holder, crucible tongs, centrifuge, wire gauze, stirring rodMaterials: steel wool, sulfur, copper mesh, (NH4)2CO3 (s), CuSO4 QUOTE 5H2O(s), zinc, 0.10 M HCl(aq), 0.10 M CuSO4(aq), 0.10 M Pb(NO3)2 (aq), 0.10 M KI(aq), 0.10 M FeCl3 (aq), 0.10 M NaOH, phenolphthalein solution, red litmus paperPart A. Fe(s) + S8(s) one product (Use lower charge for iron and balance the equation).1. Place a small amount of iron in the form of steel wool in the bottom of a crucible. The steel wool should be a thin layer that you can see through. Describe the appearance of the steel wool on the Data Sheet for Part A. 2. With a spatula, sprinkle a very small amount of sulfur on top of the steel wool in the crucible. Describe the appearance of the sulfur on the Data Sheet for Part A. 3. Place the lid on the crucible and place it on a clay triangle supported on a ring on a ring stand. Place the crucible and the ring stand under the ventilation hood. 4. Heat the crucible strongly with a Bunsen burner for at least five minutes. After five minutes, lift the lid of the crucible with crucible tongs and check to see if there is any unreacted sulfur. Be careful not to breathe fumes. If there is any unreacted sulfur, heat the crucible a few more minutes. Heat until no unreacted sulfur remains.5. Allow the crucible to cool on a wire gauze on your lab bench. When it is cool, use a stirring rod to break up the product and observe. Describe the appearance of the product on the Data Sheet in Part A and complete Part A of the Data Sheet.6. Dispose of the solid product in the solid waste container in the ventilation hood.Part B. HCl(aq) + NaOH(aq) _______ + _______(Predict products and balance equation.)USE CAUTION WITH THE ACID AND THE BASE. IF YOU SHOULD GET EITHER ONE OF THEM ON YOUR SKIN, WASH IMMEDIATELY WITH WATER AS SHOWN IN THE SAFETY VIDEO.7. Place approximately 1 mL of the 0.10 M NaOH(aq) solution in a small clean test tube and describe its appearance on the Data Sheet for Part B.8. Add one drop of phenolphthalein solution to the base in the test tube and stir with a clean stirring rod. Record the results on the Data Sheet for Part B. Phenolphthalein is an indicator which changes color if it is placed in an acidic solution or a basic solution. It is colorless in acid and bright pink in base.9. In a second small clean test tube add approximately 1.5 mL of the 0.10 M HCl(aq) solution. Add one drop of phenolphthalein solution to it and record your results on the Data Sheet for Part B. 10. Slowly, with stirring, add small portions of the 0.10 M HCl(aq) to the 0.10 M NaOH(aq) solution until there is a color change. 11. Dispose of the mixed solution and any leftover acid in the acid waste container in the ventilation hood.Part C. Cu(s) + O2(g) ____ (Predict one product. Balance the equation.)12. Place a small amount of copper mesh in a clean, dry crucible. Describe the appearance of the copper mesh on the Data Sheet for Part C.13. Place the crucible on a clay triangle supported on a ring on a ring stand. Do not put a lid on the crucible. Heat the crucible with a Bunsen burner strongly until the bottom of crucible glows red in order for the Cu to react with atmospheric oxygen, O2. It will probably take at least 5 minutes of strong heating for it to turn red.14. Remove the crucible with crucible tongs and allow it to cool on a wire gauze on your lab bench. 15. When the product is cooled to room temperature, record its appearance on the Data Sheet for Part C and complete Part C of the Data Sheet.16. Dispose of the solid product in the solid waste container in the ventilation hood. Part D. FeCl3(aq) + NaOH(aq) _______ + _______(Predict products and balance equation.) 17. Place approximately 5 drops of 0.10 M FeCl3(aq) in a small clean test tube and describe its appearance on the Data Sheet for Part D. 18. Describe the appearance of the 0.10 M NaOH(aq) solution on the Data Sheet for Part D. USE CAUTION IN HANDLING THE CORROSIVE NaOH. If you should get the base on your skin, wash immediately with water as shown in the safety video.19. Add approximately 1 mL of the NaOH solution to the FeCl3(aq) in the test tube and mix with a clean stirring rod. If the mixture does not turn cloudy, add more NaOH. Centrifuge briefly so that the solid product can be observed easier. Describe the appearance of the solid product on the Data Sheet for Part D. Complete all of Part D on the Data Sheet. 20. Dispose of the materials in the proper waste container in the ventilation hood.DIRECTIONS FOR CENTRIFUGE:DO NOT POUR CHEMICALS DIRECTLY INTO THE CENTRIFUGE; THEY SHOULD BE IN SMALL TEST TUBES. BALANCE THE CENTRIFUGE WITH A SECOND IDENTICAL TEST TUBE FILLED WITH TAP WATER TO THE SAME HEIGHT AS THE ONE CONTAINING THE PRECIPITATE.On the front panel, press the LID button to open the centrifuge. Insert the test tubes in any two slots 180o apart.Close the lid by pressing it firmly down. You will hear a locking noise.Press the SET TIME button (it displays the number 1 at first). Press the + button to set the time to 2 minutes and then press START.The centrifuge will run at a low vibration mode and will stop after 2 minutes. Do not try to open the lid. A yellow light will appear by the LID button.Press LID button only when the noise stops.Remove the test tubes without removing the plastic sleeves.Part E. (NH4 )2CO3(s) _____ + _____ + ______ (Predict products and balance the equation).21. Place a small amount of (NH4)2CO3, ammonium carbonate, in a small, dry test tube. Describe the appearance of the ammonium carbonate on the Data Sheet for Part E.22. Place a piece of red litmus paper that has been moistened with distilled water on the inside of the test tube near the top. (Red litmus turns blue in the presence of a base, such as NH3, ammonia.) The litmus paper may change color before mild heating.23. Hold the test tube with a test tube holder at an angle, aimed away from you and other people and heat the test tube gently with a Bunsen burner in the ventilation hood. Observe the solid, the inside top of the test tube, and the litmus paper immediately upon heating. 24. Remove the test tube from the heat and carefully observe the odor coming from the test tube by wafting the fumes toward you as shown in the safety video.25. Record your observations on the Data Sheet for Part E and complete all of Part E on the Data Sheet.26. If there is any solid waste, dispose of it in the solid waste container in the ventilation hood.Part F. Pb(NO3)2(aq) + KI(aq) _______ + _______(Predict products and balance equation).27. Place approximately 0.5 mL of 0.10 M Pb(NO3)2 (aq) solution in a small test tube. Describe the solution on the Data Sheet for Part F.28. Before adding KI(aq) to the test tube with the lead(II) nitrate (plumbous nitrate) solution, describe the KI solution on the Data Sheet for Part F.29. Add a few drops of the 0.10 M KI(aq) solution to the Pb(NO3)2(aq) solution in the test tube and mix with a clean stirring rod. Centrifuge briefly so that the solid product can be observed easier. Describe the appearance of the product on the Data Sheet for Part F. Complete all of Part F on the Data Sheet. 30. Dispose of the materials in the proper waste container in the ventilation hood.Part G. CuSO4 QUOTE 5H2O(s) _____ + ______ (Predict product and balance the equation).31. Place a small amount of solid CuSO4 QUOTE 5H2O, copper(II) sulfate pentahydrate (cupric sulfate penta-hydrate), in a small, dry test tube. Describe its appearance on the Data Sheet for Part G.32. Hold the test tube with a test tube holder at an angle, aimed away from you and other people and heat the test tube gently with a Bunsen burner.33. Observe the solid and the inside walls of the test tube while you are heating. Record your observations in Part G of the Data Sheet. Complete all of Part G on the Data Sheet.34. Dispose of solid waste in the solid waste container in the ventilation hood.Part H. Zn(s) + CuSO4 (aq) _______ + _______(Predict products and balance equation).35. Obtain a small piece of zinc (Zn) about the size of a pea. Place it in the bottom of a small test tube by pushing it down with a stirring rod. Describe the appearance of the zinc on the Data Sheet for Part H.36. Add approximately 2 mL of the 0.10 M CuSO4 (aq) solution to the test tube. Describe the appearance of the CuSO4 solution on the Data Sheet for Part H.37. Use a stirring rod to ensure that the Zn is in contact with the solution. After at least 5 minutes, describe the appearance of the solid and the solution on the Data Sheet for Part H. Complete all of Part H on the Data Sheet.38. Dispose of the materials in the proper waste container in the ventilation hood.Part I. Zn(s) + HCl(aq) ______ + _______ (Predict products and balance equation).39. Obtain a small piece of zinc metal and place it in a small test tube. Describe its appearance on the Data Sheet for Part I.40. Add approximately 2 mL of 0.10 M HCl to the test tube with the zinc. USE CAUTION IN HANDLING CORROSIVE HCl. If you should get acid on your skin wash with water immediately as shown in the safety video.41. Record your observations on the Data Sheet for Part I. Complete all of Part I on the Data Sheet. 42. Dispose of the acid and un-reacted metal in the proper container in the ventilation hood.LAB VII. TYPES OF REACTIONS DATA SHEETNAME:__________________________ SECTION:_____________________PART A.1. Describe the steel wool (Fe):2. Describe the sulfur (S8):3. Describe the product iron(II) sulfide (ferrous sulfide), FeS(s) after heating:4. Write and balance the chemical equation:5. Type of reaction:PART B.6. Describe the NaOH(aq) after the phenolphthalein added:7. Describe the HCl(aq) after the phenolphthalein is added:8. Write the balanced molecular equation:9. Write the ionic equation.10. Write the net ionic equation.11. Type of reaction: PART C.12. Describe the copper mesh (Cu):13. Describe the product after heating:14. Write and balance the chemical equation:15. Type of reaction:PART D. 16. Describe the iron(III) chloride (ferric chloride) solution, FeCl3 (aq):17. Describe the sodium hydroxide solution, NaOH(aq):18. Describe the product formed:19. Write the balanced molecular equation:20. Write the ionic equation.21. Write the net ionic equation.22. Type of reaction:LAB VII. TYPES OF REACTIONS DATA SHEETNAME:__________________________ SECTION:_____________________PART E. 23. Describe the ammonium carbonate, (NH4)2CO3:24. Observations of the solid during heating:25. Observation of the litmus paper during heating:26. Observation of the inside walls of the test tube during heating:27. Describe the odor:28. Write and balance the chemical equation:29. Type of reaction:PART F. 30. Describe the lead(II) nitrate (plumbous nitrate) solution, Pb(NO3)2 (aq):31. Describe the potassium iodide solution, KI(aq):32. Describe the product formed:33. Write the balanced molecular equation:34. Write the ionic equation.35. Write the net ionic equation.36. Type of reaction:PART G. 37. Describe the copper(II) sulfate pentahydrate, CuSO4 QUOTE 5H2O(s):38. Observation of the solid during heating:39. Observation of the inside walls of the test tube during heating:40. Write and balance the chemical equation:41. Type of reaction:LAB VII. TYPES OF REACTIONS DATA SHEET NAME:__________________________ SECTION:_____________________PART H.42. Describe the zinc, Zn:43. Describe the copper(II) sulfate (cupric sulfate) solution, CuSO4(aq):44. Describe the solid and liquid after 5 minutes of mixing:45. Write the balanced molecular equation:46. Write the ionic equation.47. Write the net ionic equation.48. Type of reaction:PART I.49. Describe the zinc, Zn(s):50. Observation after the hydrochloric acid, HCl(aq), is added:51. Write the balanced molecular equation:52. Write the ionic equation.53. Write the net ionic equation.54. Type of reaction: LAB VIII. PRACTICE EXERCISESNAME: ______________________SECTION:________________________Adapted from Chemistry 11th ed. by Raymond Chang and Kenneth GoldsbyPART A. CHAPTER 1 EXERCISES. SHOW YOUR WORK!!! 1. Convert a weight of 145 lbs to kilograms.2. What is the height of a person in centimeters who is 6.0 ft 2.0 in tall?3. An adult person has a blood volume of about 5200 mL. How many pints of blood is this?4. Convert a speed of 55 miles per hour to kilometers per hour. (1 mile = 1609 m)5. How many milliliters are in 1.00 cup?6. What is the area in cm2 of a sheet of paper that is 8.50 in x 11.0 in? 7. A roll of aluminum foil has a mass of 1.07 kg. What is its mass in pounds?8. A box is 252.50 cm wide, 18.25 cm tall and 6.50 cm deep. Calculate the volume of the box in liters.9. How many grams does an 8.50 ounce package weigh?10. Gas is $2.50/gal at Station A and 85 cents/L at Station B. Convert the cost of gas at Station B to $/gal. At which station would you buy gas?11. Convert body temperature of 98.6oF to Celsius.12. Osmium is the densest element known. Convert its density of 22.57 g/cm3 to lb/gal. 13. Lithium is the least dense metal known (D = 0.53 g/cm3). What is the volume occupied by 250 g of lithium?14. A fighter jet must reach a speed of 62 m/s to take off from the deck of an aircraft carrier. Calculate the speed in miles per hour. (1 mile = 1609 m)15. Convert a room temperature of 25.0 oC to oF.16. A rectangular piece of platinum has dimensions of 3.50 cm x 2.16 cm x 1.08 cm and weighs 175.5 g. What is the density of platinum?17. Convert 300 K to oF.18. The density of gasoline is 0.65 g/mL. What is the mass in pounds of 45.0 L (about 12 gal) of gasoline?19. What is the length in meters of 100 yards?20. An atomic radius is about 100 pm. Convert the radius to inches. (1pm = 10-12m) LAB VIII. PRACTICE EXERCISESNAME: __________________________SECTION:_____________________PART B. CHAPTER 3 EXERCISES1. Calculate the formula mass of Ca3(PO4)2. _______________________g/mole2. Calculate the formula mass of MgSO4.10 H2O. __________________g/mole3. What is the mass of 0.560 mole of aspirin, C9H8O4? _____________________g4. Calculate the number of moles in 100.0 g of Zn(NO3)2.___________________moles5. How many molecules are present in 75.0 g chloroform, CHCl3?________________molecules6-7. Determine percent composition of the following compounds.6. Na2CO37. (NH4)2S8. Find the empirical formula of a compound containing 52.93% aluminum, 47.84% oxygen. What is the molecular formula if the molar mass is 102 g/mole? 9. What is the empirical formula of a compound containing 27.88% phosphorus and 72.15% sulfur? Determine the molecular formula if the molar mass is 444.6 g/mole.10. What mass of KMnO4 contains 250.0 g of manganese? LAB VIII. PRACTICE EXERCISESNAME:_______________________________SECTION:_____________________PART C. CHAPTER 3 CALCULATIONS WITH BALANCED EQUATIONS 1. Balance the following equations: (a) Mg(OH)2 + H3AsO4 Mg3(AsO4)2 + H2O (b) NH4NO3 N2O + H2O (c) AsCl3 + H2O H3AsO3 + HCl (d) C4H10O2 + O2 CO2 + H2O2. Use the balanced equation, Cl2 + 3 F2 2 ClF3,How many moles of Cl2 are needed to react with 3.44 moles of F2?How many grams of ClF3 form when 0.204 moles of F2 react with excess Cl2?How many grams of ClF3 form from 130.0 grams of Cl2 when F2 is in excess?How many grams of F2 are needed to react with 3.50 grams of Cl2?3. Answer the following with this reaction: P4O10 + 6 PCl5 10 POCl3. (a) How many grams of POCl3 are produced when 225.0 grams of P4O10 and 675.0 grams of PCl5 react? (b) How many grams of excess reactant remain after the reaction in (a)? (c) When 42.66 grams of PCl5 react with excess P4O10, the amount of product formed is 47.22 grams of POCl3. What is percent yield? 4. If 12.3 grams of CCl4 are produced when 18.0 grams of CS2 reacts with 22.0 grams of Cl2, what is percent yield of CCl4? CS2 + 3 Cl2 CCl4 + S2Cl25. Use the reaction, 8 Al + 3 Fe3O4 4 Al2O3 + 9 Fe. (a) How many grams of iron are produced by the reaction of 225.0 grams of Al and 225.0 grams of Fe3O4? (b) How many grams of Al2O3 are also produced in the reaction of (a)? (c) Which reactant is in excess and how many grams remain after reaction?LAB VIII. PRACTICE EXERCISESNAME:_______________________________SECTION:_____________________PART D. CHAPTER 4 SOLUTION CONCENTRATIONS & STOICHIOMETRY 1. Calculate the molarity of a solution containing 37.8 g KBrO3 in 750 mL of solution. _________M 2. How many grams of glucose (C6H12O6) are needed to prepare 250 mL of 0.300 M C6H12O6 solution? 3. What volume of 6.00 M HNO3 solution is needed to prepare 1500 mL of 0.180 M HNO3 solution? 4. Use the reaction: 3 NaOH + H3PO4 Na3PO4 + 3 H2O a. How many mL of 0.225 M NaOH will react with 4.568 gram H3PO4? b. How many mL of 0.385 M H3PO4 react with 50.0 mL of 0.404 M NaOH? c. What is the maximum amount of Na3PO4 that is formed from the reaction of 25.00 mL of 0.1050 M NaOH and 15.00 mL of 0.08650 M H3PO4? d. What is the molarity of Na3PO4 in the solution prepared in c? 5. What volume of 0.3682 M H2SO4 solution is required to react with 0.4198 grams of Al(CN)3 according to the reaction, 2 Al(CN)3 + 3 H2SO4 6 HCN + Al2(SO4)3? 6. For the reaction: Al(OH)3 + 3HCl AlCl3 + 3 H2O a. How many grams of Al(OH)3 react with 25.00 mL of 0.1038 M HCl solution? b. What is the molarity of an HCl solution if 71.28 mL of the HCl solution react with 0.1035 g of Al(OH)3? c. What is the limiting reactant when 0.425 g of Al(OH)3 are mixed with 25.0 mL of 4.00M HCl solution? d. How many grams of AlCl3 is produced from the mixture in c? LAB VIII. PRACTICE EXERCISESNAME:_______________________________SECTION:_____________________PART E. CHAPTER 7 QUANTUM NUMBERS & ELECTRON CONFIGURATION1. Give the electron configuration for the following atoms using appropriate noble gas inner core abbreviation: Bi Cr Sr P2. Give a set of 4 possible quantum numbers for the most energetic electron(s) of:BiCrSrP n = l = ml = ms =3. What is the symbol and name of the element with the following electron configuration?SymbolName [Kr]5s24d105p2 [Xe]6s1 [Ar]4s13d10 What is the symbol and name of an element that could have the following n and l quantum numbers to describe its most energetic electron(s)? n, lSymbolName 4, 1 5, 2 2, 0 5, 3 5. Give the order that electrons fill sublevels from the 1st through the 7th period of elements.6. How many unpaired electrons do the following elements have?Number of unpaired electrons Cd K As Cr LAB IX. SEPARATING MIXTURESBefore you begin this lab be familiar with mixtures and the separation of mixtures by physical means. Background information is found in Chapter 1 of the text. In this lab you will be separating a heterogeneous mixture containing sand, table salt and chalk. All measurements and separations must be done carefully to obtain good results. Your teacher will indicate whether you are to do the experiment one or two times.Materials:Equipment: evaporating dish, ring, ring stand, wire gauzes, Bunsen burner, striker or matches, filter, filter paper, ring, beakers, Erlenmeyer flask, water bottle, electronic balance, graduated cylinder, stirring rod, watch glassReagents: Unknown mixtures of SiO2, NaCl, and CaCO3, 3 M HCl(aq), 1M K2CO3, deionized water SEPARATION OF A MIXTURE CONTAINING SiO2 , NaCl and CaCO31. Place a clean, dry beaker (150-mL) on an electronic balance and zero/tare the balance.2. Obtain an unknown mixture of sand, table salt and chalk (SiO2, NaCl and CaCO3). Stir the bottle to ensure that it is the same consistency throughout. Record its code number or letter on Data Sheet 2. 3. Add approximately 3 grams of the unknown mixture to the beaker and obtain its mass to the nearest 0.001gram. Record on the Data Sheet.4. Add approximately 50 mL of deionized water to the mixture in the beaker and stir thoroughly for 3-5 minutes with a stirring rod. The water dissolves the NaCl and not the sand or the chalk. 5. Obtain a piece of filter paper and fold it in half and then fold it in half again. Open it up so that three layers are on one side and one layer is on the other. This should make a cone. Place the cone in a funnel, dampen the filter paper with deionized water, and press the filter paper flat against the funnel, making sure there are no air bubbles trapped.6. Place the funnel with the paper in a ring supported on a ring stand. Record the mass of a 250-mL E. flask on the Data Sheet. Place the pre-weighed E. flask below the filter stem, so that it can catch the filtrate (the liquid that comes through the filter). If the stem is touching the inside of the flask below it, the liquid flows faster. 7. Filter the water and mixture, so that the salt water solution passes through the filter paper, but not the chalk and sand. Use deionized water from your water bottle to help transfer all the solid from the first beaker to the filter paper. 8. After the filtration is complete, the filtrate should be a clear solution and contain only the distilled water and the dissolved NaCl. Place the E. flask containing this clear solution on the hot plate and evaporate ALL the water. When most of the water is evaporated, lower the heat to avoid splattering or loss of NaCl. The E. flask, including the sides of the E. flask, should be dry. 9. When the E. flask containing the NaCl is completely dry and has been cooled to room temperature on a wire gauze, weigh it to the nearest 0.001 g and record the mass on Data Sheet 2. This mass allows you to determine the mass of the NaCl that was in the original sample. Do not discard the NaCl until all calculations are complete.10. Record the mass of a 250-mL beaker (beaker #2) to the nearest 0.001 g on Data Sheet 2. Wash all of the solid from the filter paper into the pre-weighed beaker #2. Use the stirring rod and a small amount of water from your water bottle to make the transfer as complete as possible. This solid contains the sand and chalk.11. Slowly add approximately 10 mL of 3 M HCl(aq) to the solid material in beaker #2. Stir as the acid is added. Continue stirring until all the bubbling stops. Add more acid if the mixture is still cloudy. The acid reacts with the chalk, CaCO3 , to produce the soluble salt, CaCl2, and CO2 gas (the bubbles). The acid does not react with the SiO2, the sand. 12. When the bubbling stops, decant the mixture, by carefully pouring the liquid off the top of the sand into a third beaker (150-mL or 250-mL beaker). Be careful not to transfer any sand. Rinse the sand two times with 3-5 mL of deionized water, each time stir the mixture and decant the rinse into beaker #3.13. Beaker #2 should contain only wet SiO2, sand at this point. Place beaker #2 with the sand on a hot plate and dry the sand. Be careful to avoid splattering or loss of sand. The beaker, including the sides of the beaker, should be dry. When the sand seems completely dry, cool the beaker on a wire gauze, weigh it, and record the mass to the nearest 0.001g on the Data Sheet. Do not discard the sand until all calculations are complete.14. The solution in beaker #3 contains the calcium from the CaCO3, chalk, in the form of soluble CaCl2. Heat the solution on a hot plate to boiling and boil gently for five minutes. Take the beaker off the hot plate and place it on a wire gauze. Slowly add approximately 15 mL of 1 M K2CO3 solution with stirring. The added K2CO3 reacts with CaCl2 to form the precipitate, CaCO3. If no white cloudiness appears, add more K2CO3 solution.15. Place a piece of filter paper on a clean, dry watch glass. Weigh the filter paper and watch glass to the nearest 0.001 g and record this weight on the Data Sheet. Then fold this filter paper and prepare as in step 5.16. When the mixture from step 14 is cool, filter the mixture through the prepared filter paper. Wash any remaining solid into the filter paper. Add an extra 3-5 mL deionized water to the solid to wash the CaCO3. The filtrate (liquid) and washings may be discarded in the acid waste. 17. Carefully remove the filter paper with the CaCO3 from the funnel. Open the filter paper and place on the preweighed watch glass. To dry the CaCO3, place the filter paper and watch glass on a water bath on a hot plate. (To prepare the water bath, add about 100 mL of water to a 250-mL beaker). Heat until the filter paper and CaCO3 are dry. Use crucible tongs to remove the watch glass with the filter paper from the water bath.18. Place the watch glass with the filter paper on a wire gauze to cool. When the watch glass has cooled to room temperature, determine the mass of the watch glass with the filter paper containing the CaCO3 to the nearest 0.001 g. Record the mass on Data Sheet 2.19. Calculate all percentages. If over 100% is recovered, one or more of the products is still damp. Reheat the sand and salt and CaCO3 samples, cool, and reweigh. % NaCl = mass of table saltmass oforiginal mixture × 100 % SiO2 = mass of sandmass of original mixture × 100% CaCO3 = mass of chalkmass of original mixture × 100% Recover = total mass of the three components recoveredmass of original mixture × 100CHEM1411 Lab IX3045460295910Filtration with Deionized H2O00Filtration with Deionized H2O297180022923500 Sample mixture of SiO2(s), CaCO3(s), and NaCl(s)1921510154305 L00 L3207385125730 S00 S29718002305050022222055189300207645022288500389572522288500NaCl(aq) SiO2(s) and CaCO3(s)39909751293783M HClDecantation003M HClDecantation95250022698Evaporation00Evaporation4197985243205 S00 S2835910233680 L00 L3093720159223001428750133350Weigh NaCl(s)020000Weigh NaCl(s) 3899062-6985004876800311150Washing and evaporation00Washing and evaporation2085975311150K2CO3(aq) 00K2CO3(aq) 304800024447500CaCl2(aq) SiO2 wet48196504635500440054960960Weigh SiO2(s)020000Weigh SiO2(s) CaCO3(s) wet3057525298450030956255715Filtration00Filtration2609849154305Weigh CaCO3(s)020000Weigh CaCO3(s)L – LiquidS – Solid 0000LAB IX. SEPARATING MIXTURESDATA SHEET NAME:_____________________SECTION:__________.1. Unknown code: _______Trial 1Trial 22. Mass of mixture, g______________3. Mass of E. flask + NaCl, g______________ (after heating to dryness)4. Mass of E. flask, g______________ 5. Mass of NaCl, g______________ ( line 3 – line 4)6. Mass of beaker #2 + SiO2, g______________ (after heating to dryness)7. Mass of beaker #2, g______________8. Mass of SiO2, g______________ (line 6 – line 7)9. Mass of watch glass + filter paper + CaCO3, g______________ (dried CaCO3)10. Mass of watch glass + filter paper, g______________11. Mass of CaCO3, g ______________ (line 9- line 10)12. % NaCl______________13. % SiO2______________14. % CaCO3______________15. % Recovery______________ Use the correct number of significant figures for your answers in #12-15.LAB X. DETERMINING AN EMPIRICAL FORMULABefore you begin this lab be familiar with the calculations to determine the empirical formula of a compound from experimental data. Background material is found in Chapter 3 of the text. Your instructor will indicate if you are to do Part A and/or Part B.94615360045You must wear appropriate clothing, shoes and safety glasses for this lab. 020000You must wear appropriate clothing, shoes and safety glasses for this lab. THERE SHOULD BE NO OPEN FLAMES IN THE LAB WHILE YOU ARE DOING PART A OF THIS LAB.PART A. DETERMINING THE EMPIRICAL FORMULA OF ZINC CHLORIDEMaterials:Equipment: evaporating dish, hot plate, wire gauze, tongs, stirring rod, graduated cylinderReagents: 6 M HCl, granular zinc 1. Place a clean, dry evaporating dish on a hot plate. Heat the evaporating dish gently at first and then strongly for approximately five minutes on the hot plate.2. At the end of the heating period, remove the dish from the hot plate with tongs and place it on a wire gauze on your lab bench to cool. When it is room temperature, record its mass to the nearest 0.001 g on the Data Sheet.3. Add approximately 0.25 g of powdered zinc to the weighed evaporating dish and reweigh the dish with the zinc. Record its mass to the nearest 0.001 g on the Data Sheet. 4. Do this step under the ventilation hood. Slowly in 2-3 mL increments, and with continuous stirring, add 15 mL of 6 M HCl to the zinc in the evaporating dish. If any zinc metal remains after the bubbling has ceased, add 5 more mL’s of the 6 M HCl. Continue adding 5 mL increments of the acid until all the zinc has reacted. (15 mL’s total will probably be enough.)5. Evaporate the solution in the evaporating dish on a hot plate. Heating gently, making sure that the solution does not splash. Be sure the hot plate is completely under the ventilation hood.6. Do not allow the solid to melt. Remove the evaporating dish from the hot plate when the solid is pasty, not completely dry.7. Allow the evaporating dish to cool on a wire gauze on your bench top until it is room temperature. Weigh it and record its mass to the nearest 0.001 g on the Data Sheet.8. Gently reheat the evaporating dish on the hot plate for a few minutes, cool it and reweigh it. Record the mass on the Data Sheet.9. Continue reheating, cooling and reweighing, until two successive readings agree within 0.05 grams. This procedure is referred to as drying to constant mass. Record the masses on the Data Sheet. 10. Complete the calculations to determine the empirical formula of zinc chloride.11. Repeat the experiment if directed by your instructor.CALCULATIONS FOR DATA SHEET:12. Determine mass of zinc.13. Determine the mass of zinc chloride.14. To determine the mass of chloride: mass of zinc chloride – mass of zinc15. Determine moles of zinc: grams of zincatomic mass of zinc16. Determine moles of chloride: grams of chlorineatomic mass of chlorine17. Determine mole ratio by dividing answers in # 15 and #16 by the smaller answer obtained in #15 and #16. 18. The numbers obtained in #17 should be close to whole numbers and these will be the subscripts for the formula in ZnxCly. You have just determined x and y for the empirical formula. If they do not come close to whole numbers, multiply each by a factor so that they are closer to whole numbers.LAB X. DETERMINING AN EMPIRICAL FORMULADATA SHEET PART A DETERMINING THE EMPIRICAL FORMULA OF ZINC CHLORIDENAME:_____________________SECTION:________________Trial #1Trial #21. Mass of evaporating dish and zinc, g______________2. Mass of evaporating dish, g______________3. Mass of zinc, g______________ (line 1 – line 2) 4. Mass of evaporating dish and zinc chloride,g (First weighing)______________ (Second weighing)______________ (Third weighing)______________5. Mass of zinc chloride, g (Final weighing)______________ (line 4 – line 2)6. Mass of chloride, g______________ (line 5 – line 3)7. Moles of zinc _______________ (Use two significant figures)8. Moles of chloride______________ (Use two significant figures)9. Empirical formula of zinc chloride______________PART B. DETERMINING THE EMPIRICAL FORMULA OF MAGNESIUM OXIDE76200253365You must wear appropriate clothing, shoes and safety glasses for this lab.00You must wear appropriate clothing, shoes and safety glasses for this lab.DO NOT PERFORM PART B IF THERE ARE STUDENTS IN THE ROOM DOING PART A OF THIS EXPERIMENT.Materials: Equipment: crucible, crucible lid, ring, ring stand, clay triangle, Bunsen burner, striker, tongs, wire gauze Reagents: magnesium ribbon, distilled water1. Place a clean crucible and lid on a clay triangle which is supported by a ring on a ring stand. Heat strongly for five minutes. 2. Remove the crucible and lid from the clay triangle with tongs and allow them to cool on a wire gauze on your bench top.3. When the crucible and lid are room temperature, weigh them together to the nearest 0.001 g and record the mass on the Data Sheet. 4. Obtain approximately 35-40 cm of magnesium ribbon. It should be shiny silver. If it is dull, clean it by rubbing it with steel wool. 5. Make a loose coil of the magnesium ribbon by coiling it around a pencil. Place the magnesium coil in the weighed crucible, place the lid on and weigh to the nearest 0.001 g. Record the mass on the Data Sheet.6. Place the crucible with the magnesium on the clay triangle over the Bunsen burner. Place the lid on, but cracked open slightly. Heat the crucible with the magnesium first very gently and then strongly for 15 minutes. If you notice bright light or smoke from the crucible, remove heat momentarily and heat slower. The magnesium reacts with the oxygen in the air. Perform this procedure under the ventilation hood.7. After the 15 minute heating period, remove the crucible and lid with tongs from the clay triangle and allow them to cool on the wire gauze on your lab bench. If the magnesium appears unreacted, heat it for a longer period.8. When the crucible is room temperature, add enough deionized water to cover the magnesium residue. 9. Heat the crucible, water and residue (with the lid cracked open) strongly for five minutes. Any magnesium nitride that may formed is converted into magnesium oxide in a two-step reaction. (Magnesium may react with nitrogen in the air, as well as oxygen.)10. Remove the crucible and lid from the clay triangle and allow them to cool on the wire gauze on your lab bench. 11. When the crucible and lid are room temperature, weigh them to the nearest 0.001 g and record the mass on the Data Sheet. Do not discard the solid until you check your calculations. If the answer does not agree with what you think it should be, based on charges of the probable ions formed, reheat the residue some more, cool and reweigh.CALCULATIONS:12. Determine mass of magnesium.13. Determine mass of magnesium oxide.14. To determine mass of oxygen: mass of magnesium oxide – mass of magnesium15. Determine the moles of magnesium: grams of magnesiumatomic mass of magnesium16. Determine moles of oxygen: grams of oxygenatomic mass ofoxygen17. Determine mole ratio by dividing answers in #15 and #16 by the smaller answer obtained in #15 and #16. 18. The numbers obtained in #17 should be close to whole numbers and these will be the subscripts for the formula MgxOy. You have just determined x and y for the empirical formula. If they are not close to whole numbers, multiply each by a factor so that they are whole numbers.LAB X. DETERMINING AN EMPIRICAL FORMULADATA SHEET PART BDETERMINING THE EMPIRICAL FORMULA OF MAGNESIUM OXIDENAME:_____________________SECTION:________________Trial #1Trial #21. Mass of crucible, lid and Mg, g______________2. Mass of crucible and lid, g______________3. Mass of magnesium, g______________ (line 1 – line 2)4. Mass of crucible and magnesium oxide ,g______________ (AFTER WATER TREATMENT AND COOLING) 5. Mass of magnesium oxide, g ______________ (line 4 – line 2)6. Mass of oxygen, g______________ (line 5 – line 3)7. Moles of magnesium _______________ (Use two significant figures)8. Moles of oxygen______________ (Use two significant figures)9. Empirical formula of magnesium oxide______________LAB XI. DOUBLE DISPLACEMENT REACTIONSBefore you begin this lab be familiar with the types of reactions found in Chapter 4 of the text. The four major types are: combination (also called composition), decomposition, single displacement (called displacement in the text), double displacement (also called metathesis). Double displacement includes both neutralization reactions and precipitation reactions. Oxidation-reduction (redox) reactions include many of the other types of reactions. Evidence that a chemical reaction has occurred include: a color change, the formation of a gas, the formation of a solid, a precipitate. In this lab you will study precipitation reactions, one of the types of double displacement reactions. You will combine known reagents and look for evidence of reaction, a precipitate, with these reactions. After observing reactions of known reagents, you will perform reactions with unknown reagents. By comparing the reactions of unknowns with the reactions of known reagents, you will identify the unknowns. The solubility of precipitates in 1M CH3COOH will also tested.2857511430Wear appropriate clothing, shoes and safety glasses.020000Wear appropriate clothing, shoes and safety glasses.Materials:Equipment: 2 well platesReagents: 1.0 M CH3COOH, tray of six 0.1 M Known salt solutions, tray of six 0.1 M Unknown salt solutions PART A: DOUBLE DISPLACEMENT REACTIONS OF KNOWN SOLUTIONS1. Select a tray of A Known solutions, B Known solutions, or C Known solutions. Use the Known solutions in Part A. 2. Clean two well plates with soap and tap water. Rinse the well plates with tap water, then with deionized water and dry with paper towel. The well plates must be VERY clean for this lab to work well. ALL SOAP SHOULD BE RINSED OUT OF THE WELLS. 3. Write the formulas of the six Known salt solutions in your tray across the top row on Data Sheet 1. Then write the formulas of these solutions down the first column of the table IN THE SAME ORDER. 4. Place the well plate on the black top of the lab bench with one well plate directly above the other to have six columns across and the eight rows down. 5. The chemicals will be mixed in a grid as shown on Data Sheet 1. 6. Place five drops of the chemical listed for the first horizontal row in all the wells in the first row for a total of six wells across (A1, A2, A3, A4, A5, A6). 7. Continue adding 5 drops of each reagent listed in a row to the wells 1 6 across the row. 8. Now go back and add reagents to the wells in the vertical columns. Place 5 drops of the reagent listed for the first vertical column to all wells in the first column for a total of six wells down the column (A1, B1, C1, D1, E1, F1). You may skip the wells that have the same chemical. 9. Continue to place 5 drops of each reagent listed at the top of the column to wells A F down the column.10. All wells (except for the diagonal on Data Sheet 1) should now have 10 total drops. Gently swirl the well plates on the lab bench to mix the solutions in the wells. The precipitates should form fairly quickly.11. Record on the table of Data Sheet 1 which wells contain white precipitates (white solid material or white cloudiness). Also, describe the amount and the texture of the precipitate. Note for each horizontal row how many precipitates form and write this number on the right side of the table.12. In each well containing any precipitate after mixing, add 5 drops of 1 M CH3COOH, acetic acid. Mix the acid with the precipitate by gently swirling the well plate on the lab bench for about two minutes. Record on the table of Data Sheet 1 if the precipitate dissolves in the acid. 13. On Data Sheet 2 write the balanced molecular equation, ionic equation, and the net ionic equation for each combination of reagents that produced a white precipitate (before adding acetic acid). 14. Dispose of the materials in the well plates in the appropriate waste container. PART B. 15. Select Unknown I, II, III, or IV from the Known Group you worked with in Part A. For Part B, use these unknown solutions from the Unknown tray you selected. These unknown solutions are the same chemicals that you used in Part A. You are to determine which known salt solution from Part A matches each unknown solution. 16. Clean the two well plates with soap and tap water. Rinse the well plates with deionized water and dry with paper towel. The well plates must be VERY clean for you to correctly identify your unknown solutions. Be certain that NO SOAP REMAINS IN THE WELLS. 17. Write the identifying number of the six unknown salt solutions from your tray across the top row on Data Sheet 3. The six identifying numbers should go across the top row of the table and down the first column of the table IN THE SAME ORDER. 18. Place the well plates on the black top of the lab bench with one well plate directly above the other to have six columns across and the eight rows down. 19. The chemicals will be mixed in a grid as shown on Data Sheet 3. 20. Place five drops of your unknown number 1 in all six wells across the first horizontal row (A1, A2, A3, A4, A5, A6). 21. Continue to add five drops of the indicated unknown number to all six wells in each row. 22. Now go back and add reagents to the wells in the vertical columns. Place 5 drops of the unknown number 1 listed for the first vertical column to all wells in the first column for a total of six wells down the column (A1, B1, C1, D1, E1, F1). You may skip the wells that have the same chemical. 23. Continue to place 5 drops of each indicated unknown number listed at the top of the column to wells A F down each column.24. All wells (except for the diagonal on Data Sheet 1) should now have 10 total drops. Gently swirl the well plates on the lab bench to mix the solutions in the wells. The precipitates should form fairly quickly.25. Record on the table of Data Sheet 2 which wells contain white precipitates (white solid material or white cloudiness). Also, describe the amount and the texture of the precipitate. Note for each horizontal row how many precipitates form and write this number on the right side of the table.26. In each well containing any precipitate after mixing, add 5 drops of 1 M CH3COOH, acetic acid. Mix the acid with the precipitate by gently swirling the well plate on the lab bench for about two minutes. Record on the table of Data Sheet 2 if the precipitate dissolves in the acid. 27. For each unknown number in Part B, identify the known solution from Part A that matches the results you obtained. You will determine the unknown by comparing how many precipitates you formed with each solution and the solubility of the precipitate in CH3COOH. Record your results on Data Sheet 4.28. Return the tray of solutions to the cart. Dispose of the materials in the well plates in the appropriate waste container. Clean the well plates with soap and water.LAB XI. DOUBLE DISPLACEMENT REACTIONSDATA SHEET 1 (PART A KNOWN SOLUTIONS) NAME:___________________________ SECTION:___________________Known Group Letter__________________SOLUTION123456AXBXCXDXEXFX* No need to test reagent with itself.LAB XI. DOUBLE DISPLACEMENT REACTIONSDATA SHEET 2 (PART A KNOWN SOLUTIONS)NAME:___________________________ SECTION:___________________ Write the BALANCED MOLECULAR EQUATION, IONIC EQUATION, and NET IONIC EQUATION for the mixtures that produce precipitates in Part A (before the acid is added). You will have duplicates of each mixture that forms a precipitate. Write the reaction only once. LAB XI. DOUBLE DISPLACEMENT REACTIONSDATA SHEET 3 (PART B UNKNOWN SOLUTIONS) NAME:___________________________ SECTION:___________________ Group _____ Unknown ____ (A, B, or C) (I, II, III, or IV)SOLUTION123456AXBXCXDXEXFX*No need to test reagent with itself.LAB XI. DOUBLE DISPLACEMENT REACTIONSDATA SHEET 4 (PART B UNKNOWN SOLUTIONS)NAME:___________________________ SECTION:___________________ Group _____ Unknown ____ (A, B, or C) (I, II, III, or IV)IDENTITY OF SALT * Unknown 1: ________________Unknown 2:________________Unknown 3:________________Unknown 4:________________Unknown 5:________________Unknown 6:________________*Use correct formulas.LAB XII. SINGLE DISPLACEMENT REACTIONS0504825Wear appropriate clothing, shoes and safety glasses for this lab.00Wear appropriate clothing, shoes and safety glasses for this lab.Before you begin this lab, you should be familiar with types of reactions found in Chapter 4 of the text. Materials:Equipment: 2 well platesRegents: A tray containing the metals Mg, Pb, Cu, Zn, Fe, 1.0 M HCl and 0.25 M nitrate salt solutions of each of these metals.Part A. Appearance of Metals and Reaction of Each with 1.0 M HCl.Place two well plates on a piece of white paper one directly above the other in order to have eight rows of wells. Put small pieces of the metals in the wells as follows so that the pieces of metal make a horizontal row in the bottom well-plate, #2.Mg in D-1 (second well plate)Pb in D-2 (second well plate)Cu in D-3 (second well plate)Zn in D-4 (second well plate)Fe in D-5 (second well plate)Write a brief description of each metal on Data Sheet 1. Using the dropper bottle of 1.0 M HCl from your tray, add enough acid to each well to completely cover the metal. Observe each well and note any reaction. Is a gas produced? Is there a color change? Does a new solid form? Is the reaction slow or fast? Record your observations on Data Sheet 2. Also observe each well after twenty minutes. If a reaction occurs, write the balanced molecular equation on Data Sheet 2. (Your instructor may direct you to write the ionic equation.) After twenty minutes, you may discard the acid solutions and metals in the appropriate waste container.Part B. Reaction of Metals with Metal Ion Solutions.Again use the two well plates and set up a matrix as shown on Data Sheet 3. (Part A reactions may be left in the lowest row for later observation.) Add enough solution in each well to cover a piece of metal added later. Place magnesium nitrate solution in six wells in the first vertical column. Place lead(II) nitrate solution in six wells in the second vertical column. Place copper(II) nitrate solution in six wells in the third vertical column. Place zinc nitrate solution in six wells in the fourth vertical column. Place iron(III) nitrate solution in six wells in the fifth vertical column. Write a brief description for each solution on Data Sheet 1 to complete it. Quickly add the metals as follows: Add a small piece of magnesium metal to each solution in row 1 (A-1 through A-5). Add a small piece of lead metal to each solution in row 2 (B-1 through B-5)Add a small piece of copper metal to each solution in row 3 (C-1 through C-5)Add a small piece of zinc metal to each solution in row 4 (D-1 through D-5)Add a small piece of iron metal to each solution in row 5 (A-1 through A-5, 2nd well plate)The sixth row will be used to compare to the reacting solutions.YOU MAY OMIT PUTTING METAL INTO ITS OWN SALT SOLUTION. SEE DATA SHEET 3.Observe each well and note any reaction. Is there a color change? Is a new solid formed? Is the reaction slow or fast? Record your observations on Data Sheet 3. Observe each well after twenty minutes. Compare the color of the reacting solutions to the unreacted solution in the sixth row. If a reaction occurs, write the balanced molecular equation on Data Sheet 4. (Your instructor may direct you to write the ionic equation.) After twenty minutes, discard the solutions and metals in the appropriate waste container. Based on your results, which is the most active metal? Which is the least active metal? Put your results on Data Sheet 4. Compare your results to the results in Figure 4.16 in the text on page 143.LAB XII. SINGLE DISPLACEMENT REACTIONSDATA SHEET 1NAME: __________________________ SECTION:_______________APPEARANCE OF REACTANTSMETAL/SOLUTIONAPPEARANCE Magnesium metal, MgLead metal, PbCopper metal, CuZinc metal, ZnIron metal, FeMagnesium nitrate solutionLead(II) nitrate solutionCopper(II) nitrate solutionZinc nitrate solutionIron(III) nitrate solutionLAB XII. SINGLE DISPLACEMENT REACTIONSDATA SHEET 2NAME: __________________________ SECTION:_______________MetalReaction with HClInitiallyReaction with HClAfter 20 MinutesBalanced Molecular Equation for Those Which React **MgPbCuZnFe**Bubbles must appear to indicate displacement of the hydrogen as gas.LAB XII. SINGLE DISPLACEMENT REACTIONSDATA SHEET 3NAME: __________________________ SECTION:_______________MetalMg(NO3)2 Pb(NO3)2Cu(NO3)2Zn(NO3)2Fe(NO3)3MgXPbXCuXZnXFeXINCLUDE INITIAL OBSERVATIONS AND OBSERVATIONS AFTER 20 MINUTES. RECORD IF THERE ARE ANY COLOR CHANGES OF THE METAL OR OF THE SOLUTION.LAB XII. SINGLE DISPLACEMENT REACTIONSDATA SHEET 4NAME: __________________________ SECTION:_______________Complete the following equations and balance. If no reaction occurred, mark it as NR for no reaction. All salts are in aqueous solution and all metals are 2+ in the salts except for Fe which is 3+.Mg + Pb(NO3)2 _____________________2. Mg + Cu(NO3)2 ____________________3. Mg + Zn(NO3)2 ____________________4. Mg + Fe(NO3)3 ____________________5. Pb + Mg(NO3)2 ____________________6. Pb + Cu(NO3)2 _____________________7. Pb + Zn(NO3)2 ______________________8. Pb + Fe(NO3)3 ______________________9. Cu + Mg(NO3)2 ______________________10. Cu + Pb(NO3)2 ______________________11. Cu + Zn(NO3)2 ______________________12. Cu + Fe(NO3)3 ______________________13. Zn + Mg(NO3)2 ______________________14. Zn + Pb(NO3)2 _______________________15. Zn + Cu (NO3)2 ______________________16. Zn + Fe(NO3)3 _______________________17. Fe + Mg(NO3)2 _______________________18. Fe + Pb(NO3)2 _______________________19. Fe + Cu(NO3)2 _______________________20. Fe + Zn(NO3)2 _______________________WHICH IS THE MOST ACTIVE METAL? _______________WHICH IS THE LEAST ACTIVE METAL?_______________LAB XIII. QUALITATIVE ANALYSIS The purpose of this qualitative analysis lab is to determine what ions are present in a solution. To test for an ion, it must first be separated from other similar ions and then tested. The separations are based on solubility differences. The ions you will test are Ag+, Hg22+, and Pb2+. This lab will consist of two parts. In Part A, you will follow the flow chart on the next page with ten drops of a known solution which contains all three ions. In Part B, you will be assigned an unknown solution which can contain one, two or all three ions. You will use ten drops of the unknown solution and follow the flow chart in exactly the same way. Report your observations and your conclusion about which ions are present in your unknown solution on the Data Sheet.Materials:Equipment: centrifuge, small test tubes, stirring rods, Beral pipets, hot platesmall beaker, stirring rod Reagents: distilled water, 6 M HCl, 6 M NH4OH, 1 M KI, 6 M HNO3,known and unknown solutions, litmus paperDIRECTIONS FOR CENTRIFUGE:DO NOT POUR CHEMICALS DIRECTLY INTO THE CENTRIFUGE; THEY SHOULD BE IN SMALL TEST TUBES. BALANCE THE CENTRIFUGE WITH A SECOND IDENTICAL TEST TUBE FILLED WITH TAP WATER TO THE SAME HEIGHT AS THE ONE CONTAINING THE PRECIPITATE.On the front panel, press the LID button to open the centrifuge. Insert the test tubes in any two slots 180o apart.Close the lid by pressing it firmly down. You will hear a locking noise.Press the SET TIME button (it displays the number 1 at first). Press the + button to set the time to 2 minutes and then press START.The centrifuge will run at a low vibration mode and will stop after 2 minutes. Do not try to open the lid. A yellow light will appear by the LID button. Press LID button only when the noise stops.Remove the test tubes without removing the plastic sleeves.Lab XIII: Qualitative AnalysisBegin with 10 drops of the Known solution, which contains Ag+, Hg22+ and Pb2+, in a small test tube.251460015240000Step #1 Add 4 drops of 6M HCl to the 10 drops of solution. Stir well. Separate with centrifuge. Draw off liquid with Beral pipet.400050063500020402556350002040255635000 solid liquidSolution (Acid Waste)AgCl, Hg2Cl2, PbCl2(precipitate)2040255381000 Step #2 Add 5mL hot deionized H2O Stir well. Separate quickly with centrifuge.Draw off liquid with Beral pipet and place in a small test tube.158305515494000400050015494000158305515494000 solid liquid (into clean test tube) AgCl, Hg2Cl2 (precipitate) Pb2+40005003175001583055952500 Step #3 Add 10 drops Step #5 Add 2-3 drops of KI 6M NH4OH Stir well. Separate with Yellow precipitate centrifuge. Draw off liquid indicates Pb2+ present. with Beral pipet. (Solid and Acid Waste)285750042545001125855425450011258554254500 solid liquid (into clean test tube) Ag+28575003111500Step #4 Add 6M HNO3 Dark precipitate until acidic ~ 10 dropsindicates Hg22+ present Test for acidity with blue litmus paper.(Solid and Base Waste) It will turn red in acid. Cloudy white solution (precipitate) indicatesAg+ present. (Solid and Acid Waste)Repeat steps 1-5 using 10 drops of Unknown solution in place of Known solution. Pour all waste into appropriate waste containers.DATA SHEET LAB XIII. QUALITATIVE ANALYSISNAME:__________________SECTION:_______PART A.OBSERVATIONS FOR KNOWN SOLUTION:Step 1:Step 2:Step 3:Step 4:Step 5:PART B.UNKNOWN RESULTS Unknown Number: ____________Ions PresentNot PresentEvidence for Presence of IonPb2+________________Hg22+________________Ag+________________LAB XIV. MOLECULAR AND POLYATOMIC ION SHAPES AND BONDINGAdapted from Chemistry 11th ed. by Raymond Chang.NAME: _________________________________________SECTION:___________In this lab, you will draw the Lewis structure of molecules and polyatomic ions and determine the number of Bond Pairs (BP) and Lone Pairs (LP) around the central atom. You will predict Electronic Geometry, bond angles, Molecular Geometry, polarity, and hybridization of the central atom. Before you begin this lab, look over the material on writing Lewis structures, the Valence Shell Electron Pair Repulsion Theory, VSEPR, and the Valence Bond Theory, VB, found in Chapter 9 and 10 of the text. BUILD THE FIVE BASIC SHAPES WITH MOLECULAR MODELS BEFORE YOU START THIS LAB. Refer to Table 10.1, p. 416, for these five shapes and bond angles in each shape. The Electronic Geometry, or arrangement of electron pairs, is determined from the total electron pairs around the central atom (Bond Pairs + Lone Pairs). Note that the Electronic Geometry and the Molecular Geometry are the same when the central atom has no Lone Pairs.Table 10.2, p. 422, has the Molecular Geometry of molecules and ions that have one or more Lone Pairs on the central atom.Refer to Table 10.4, p. 438, for the hybrid plete the following tables for the twenty molecules and polyatomic ions listed. Substance Lewis StructureElectronic GeometryBond AngleMolecular GeometryPolar/NonpolarHybridizationNCl3 BP____ + LP____ = ____HCNBP____ + LP____ = ____H2SeBP____ + LP____ = ____CO2BP____ + LP____ = ____NH4+BP____ + LP____ = ____SubstanceLewis StructureElectronic GeometryBond AngleMolecular GeometryPolar/NonpolarHybridizationBeBr2 BP____ + LP____ = ____OF2BP____ + LP____ = ____IF4-BP____ + LP____ = ____AlCl3BP____ + LP____ = ____XeF2BP____ + LP____ = ____Substance Lewis StructureElectronic GeometryBond AngleMolecular GeometryPolar/NonpolarHybridizationSCl2 BP____ + LP____ = ____BrF3BP____ + LP____ = ____SeF4BP____ + LP____ = ____BrF5BP____ + LP____ = ____C2H4 Treat one C as the central atomBP____ + LP____ = ____Substance Lewis StructureElectronic GeometryBond AngleMolecular GeometryPolar/NonpolarHybridizationSO32- BP____ + LP____ = ____NO3- BP____ + LP____ = ____H2COTreat C as the central atomBP____ + LP____ = ____CH2Cl2BP____ + LP____ = ____ICl3BP____ + LP____ = ____LAB XV. BOYLE’S LAWThe objective of this experiment is to determine the relationship between the pressure and volume of a gas. The gas will be air and will be confined in a syringe that is connected to a gas pressure sensor. When the volume of the gas is changed by moving the plunger, the pressure exerted by the gas changes. You will assume that temperature is constant throughout the experiment. The pressure and volume data will be graphed to show the mathematical relationship between pressure and volume of the gas sample. This relationship was first established by Robert Boyle in 1662 and is called Boyle’s Law. By using the ideal gas law and your volume and pressure data you will determine the number of moles of gas present in each air sample. Materials:Equipment: 60 mL syringe with T tube attached, Tygon tubing attached to one opening of the tube, and a stopcock inserted into the other opening of the tubePreparation of Pressure Sensor1. Record the barometric pressure on the Data Sheet and convert to atmospheres of pressure.2. Record the room temperature to the nearest 0.1oC and convert to Kelvin.3. Adjust the plunger of the syringe to 30 mL and attach the tubing to the pressure sensor on the Microlab interface.center0Note: The volume of the T tube system is approximately 3 ml. Be sure to add 3 mL to each volume reading on the syringe in Collecting Data.00Note: The volume of the T tube system is approximately 3 ml. Be sure to add 3 mL to each volume reading on the syringe in Collecting Data.4. Log in to your computer and click on All Programs. Click on MicroLab_5_9_10 and then click on the MicroLab icon.5. In Choose Experiment, click on Gas Laws. Click on Boyle’s Law and OK.6. With the stopcock attached to the syringe open, check that the pressure is the same (or within 2%) as the pressure reading from the barometer. (If it is not, contact your instructor). Collecting Data Small volume7. Move the plunger to 15.0 mL. Close the stopcock. (15 mL will be the return volume for all measurements in this section).8. Click on Start.9. One student presses the syringe in to 10.0 mL volume while the other student enters the syringe volume + 3 mL on the keyboard and presses Enter.10. Release the plunger, open the stopcock, adjust the plunger to exactly 15.0 mL again, and enter the syringe volume + 3 mL on the keyboard and press Enter. Close the stopcock.11. One student pulls the syringe out to 20.0 mL volume while the other student enters the syringe volume + 3 mL on the keyboard and presses Enter.12. Repeat Step 11 for all volumes of 25 through 50 mL at 5 mL increments of the syringe.13. Click on Stop.14. Click on Name to Print. Type “Small Volume” with your initials.15. Click on Spreadsheet and click on Print this Spreadsheet16. Right click on the graph. Under Graph Properties in Graph Title type “Small Volume Press/1/P vs Vol”with your initials and click OK.17. Right click on the graph and click on Print this Graph.18. Click on Repeat this Experiment.Middle Volume17. Use 30 mL as the return volume. Repeat Steps 8-13 for 20 mL through 60 mL at 5 mL increments of the syringe.18. Follow Steps 14-17 for Middle Volume spreadsheet and graph.19. Click on Repeat this Experiment.Large Volume20. Use 45 mL as the return volume. Repeat Steps 8-13 for 30 mL through 60 mL at 5 mL increments of the syringe.21. Follow Steps 14-17 for Large Volume spreadsheet and graph. LAB XV. BOYLE’S LAW DATA SHEETNAME: ___________________________________SECTION: ____________1. Atmospheric Pressure, mmHg____________2. Atmospheric Pressure, atm____________3. Room Temperature, oC____________4. Room Temperature, K____________5. What variables are plotted in each curved graph? (Keyboard, Kbd, is not a variable). The relationship demonstrated in this experiment in each of these curved graphs is: As _______________ increases, ________________ _________________. (variable) (variable) (increases, decreases)6. What variables are plotted in each of the “linear” graphs? What relationship is demonstrated in each of these “linear” graphs? Small Volume, moles (Use PV = nRT) Use correct units.7. Moles of gas at 18 mL____________8. Molecules of gas at 18 mL. (Use Avogadro’s number).____________Middle Volume, moles (Use PV = nRT)9. Moles of gas at 33 mL____________10. Molecules of gas at 33 mL____________Large Volume, moles (Use PV = nRT)11. Moles of gas at 48 mL____________12. Molecules of gas at 48 mL____________13. At what volume will 3.0 x 10-3 moles of gas be present at this same temperature and pressure?____________LAB XVI. MOLAR MASS DETERMINATION(DUMAS METHOD)Before you begin this lab, you should be familiar with the ideal gas law in Chapter 5 of the text. Adapted from a lab written by J. I. Gelder, N.S. Gettys and I. D. Eubanks.Materials:Equipment: 125 mL flask, 2 in square piece of aluminum foil, large graduated cylinder, 600 mL beaker, hot plate, pin, electronic balances, clamp, ring stand, thermometer, thermometer clamp, barometer or means of determining the barometric pressure, wire gauzeReagents: water, unknown liquid, boiling chipsright358140Caution: Most of the unknown liquids are flammable. Wear appropriate clothing, shoes and safety glasses.020000Caution: Most of the unknown liquids are flammable. Wear appropriate clothing, shoes and safety glasses.1. Place a boiling stone in a 125-mL flask. Fit a 2 in square piece of aluminum foil over the mouth of flask and secure with a rubber band. Make a small hole in the middle of the foil with a pin.2. Weigh the flask with the boiling stone and foil on an electronic balance and record its mass to the nearest 0.001 g on the Data Sheet.3. Prepare a hot water bath by filling a 600 mL beaker half full of tap water. Put the beaker on a hot plate and place a thermometer in the water bath. Attach the thermometer to a ring stand with a thermometer clamp. (The thermometer should not touch the bottom of the beaker).4. Obtain an unknown liquid and record its code number or letter on the Data Sheet. Carefully remove the foil from the flask and add 2 mL of the unknown liquid to the flask. Secure the aluminum foil cap around the top of the flask again.5. Place a clamp around the neck of the flask. Place the flask into the water bath as far as possible and secure it to the ring stand with the clamp. The flask should be almost totally submerged; HOWEVER, DO NOT LET THE WATER COME IN CONTACT WITH THE ALUMINUM FOIL. 6. Turn the hot plate on high. When the water temperature is approximately 45oC, turn the hot plate down to a medium heat setting. Keep the water temperature between 60-65oC. (To maintain this temperature, add ice water to the water bath if necessary).7. Watch the unknown liquid inside the flask. The vaporizing liquid will escape through the pin hole in the foil. Before the liquid is totally vaporized, the boiling stone will be surrounded by a ring of liquid. When this ring disappears, the liquid has completely vaporized. Quickly remove the flask from the hot water bath. Set the flask on a wire gauze to cool. You may also run cool water over the outside of the flask to cool it quicker, but be careful not to let the aluminum foil get wet.8. Record the temperature of the hot water to the nearest 0.1 oC on the Data Sheet and convert it to Kelvin. You may read the temperature immediately before or after you take the flask out of the water bath. (Assume the temperature of the hot water is the temperature of the vapor of the unknown liquid). 9. Record the barometric pressure on the Data Sheet and convert it to atmospheres of pressure. (Because the flask is open to the atmosphere, pressure outside the flask should be the same as inside the flask; therefore, the barometric pressure = pressure of the gas). 10. After the flask is room temperature, wipe off any water that is clinging to the outside of the flask or the aluminum foil. The outside of the flask and the foil must be dry.11. Weigh the flask and aluminum foil and any liquid that has condensed inside the flask to the nearest 0.001 g and record the mass on the Data Sheet. The condensed liquid can be placed in the waste container on the center table. 12. Repeat the experiment one or two times as your instructor indicates.13. After you have completed the number of required repetitions, take the foil off the flask and fill the flask to the very top with tap water. Pour the water into a large graduated cylinder to determine its volume to the nearest mL. Record the volume on the Data Sheet. Repeat the volume determination in this manner two more times. (This volume is the volume occupied by the gas). THE VOLUME WRITTEN ON THE FLASK SHOULD NOT BE USED. 14. Calculate the molar mass of the gas.CALCULATIONS:15. Solve for moles of the gas, n, using the ideal gas law: PV = nRT P = barometric pressure converted to atmospheres, #8 on Data Sheet V = volume of the flask in liters, #11 on Data Sheet T = temperature of the water bath, #6 on Data Sheet R = ideal gas constant, 0.0821 L atm/ mole QUOTE K, 16. Calculate the Molar Mass (MM) of the gas. MM = mass of gasmole = g gas, #4 on Data Sheetn, calculated above The mass of gas that occupies the volume of the flask at the temperature of the experiment is found on line #4 of the Data Sheet. (Any excess gas escapes through the pin hole in the foil. When the flask is cooled, the vapor inside the flask condenses).17. If your instructor provides the MM of the unknown, calculate percent error:Percent error = accepted value-your valueaccepted value QUOTE 100LAB XVI. MOLAR MASS OF A GASDATA SHEETNAME:___________________________ SECTION:____________1. Unknown sample number or letter:_______Trial 1Trial 2Trial 32. Mass of flask, foil, and sample, g (after heating)_____________________3. Mass of flask and foil, g_____________________ (before heating,without liquid)4. Mass of sample, g_____________________ (line 2 – line 3)5. Temperature of hot water, oC_____________________6. Temperature of hot water, K_____________________7. Atmospheric pressure_______ 8. Atmospheric pressure, atm_______9. Volume of flask, mL_____________________10. Volume of flask, L_____________________11. Average volume of flask, L_______12. Moles of gas (using Ideal Gas Law)_____________________13. Molar mass of the sample, g/mole_____________________ 14. Average MM of the sample, g/mole_______ 15. Accepted value of MM of the sample, g/mole_______ (If your instructor provides the MM.)16. Percent error_______LAB XVII. ACID-BASE REACTIONSBy Claire ConboyNeutralization reactions are the combination of an acid and base to produce the corresponding salt and water. In some cases that involve the neutralization of a carbonate, CO2 will also be produced as a gas. A common example of this type of reaction is the addition of acetic acid (vinegar) to sodium bicarbonate (baking soda).This experiment will demonstrate the concept of acid-base neutralization. The procedure introduces the practical application of this reaction to determine the concentration of an acid solution. Ideally, analytical burets are used to titrate solutions and provide an accurate measure of the volume dispensed. This lab procedure will utilize graduated pipets to dispense and measure volumes of solutions.Materials:Equipment: 2 graduated pipets, pipettor, Erlenmeyer flasks, stir plate and stir barReagents: Standardized NaOH solution, H2SO4 solution, phenolphthalein (or Bromthymol blue)Procedure:1. Obtain the reagents and equipment for the lab experiment.2. Using the graduated pipet, add exactly 10.0 mL of the standardized NaOH solution to an Erlenmeyer flask. Add a few drops of the indicator (phenolphthalein or bromthymol blue) to the solution and note the color. Add a stir bar to the flask and set the flask on a stir plate.3. Using a second graduated pipet, fill the pipet with approximately 10 mL of the H2SO4 solution provided. Note the exact volume of the solution in the pipet and record on the Data Sheet. Begin gradually adding the H2SO4 solution to the NaOH solution in the Erlenmeyer flask, which is being stirred on the stir plate. When you observe a color change after an addition, slow down the addition of the H2SO4 to drops. Continue adding the acid solution until the color change persists. Record the final volume of H2SO4 added on the Data Sheet.4. Repeat steps 2 and 3 at least 3 times or until the variation of the volumes of the acid is 0.3 mL or less (Line 10 on the Data Sheet).LAB XVII. ACID-BASE REACTIONSDATA SHEET NAME:___________________________ SECTION:____________1. Write a balance chemical equation for the reaction of NaOH and H2SO4.2. Molarity of the standardized NaOH solution ______________3. Moles of NaOH in 10.0 mL of solution ______________4. Label of H2SO4 solution ______________5. Color of solution after addition of Indicator ______________6. Neutralization Trials (at least 3)Trial 1Trial 2Trial 3Trial 4Initial Volume of H2SO4Final Volume of H2SO4Volume H2SO4Added7. Color of solution after neutralization _______________8. Highest volume of H2SO4 added_______________9. Lowest volume of H2SO4 added_______________10. Difference in volumes of H2SO4 added_______________ (Subtract #9 from #8. If the difference is greater than 0.5 mL, repeat trial)11. Average of H2SO4 volumes added_______________12. Moles of H2SO4 added_______________13. Molarity of H2SO4 solution_______________ ................
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