Qualitative Analysis: Group ISlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group IGeneral Chemistry 101/102General Chemistry 101/102Laboratory ManualLaboratory ManualUniversity of North Carolina WilmingtonUniversity of North Carolina WilmingtonCHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•PurposePurposeTo study the chemical properties of AgTo study the chemical properties of Ag++, Pb, Pb2+2+, and , and HgHg222+2+ ions and the compounds they form. ions and the compounds they form.Use the chemical properties of these ions to separate Use the chemical properties of these ions to separate and identify their presence in an unknown mixture.and identify their presence in an unknown mixture.•Safety ConsiderationsSafety ConsiderationsPbPb2+2+ and Hg and Hg222+2+ ions are very toxic. ions are very toxic.Wash your hands thoroughly after this experiment.Wash your hands thoroughly after this experiment.Place all waste solids and solutions in the Place all waste solids and solutions in the appropriately labeled containers in the hood.appropriately labeled containers in the hood.CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•General ProceduresGeneral ProceduresUse clean glassware and deionized water to avoid contaminating your sample.Use clean glassware and deionized water to avoid contaminating your sample.Perform each test to your known and unknown solutions simultaneously for Perform each test to your known and unknown solutions simultaneously for comparison.comparison.Distinguish between Distinguish between clear, cloudy, colored, clear, cloudy, colored, and colorless in your and colorless in your descriptions.descriptions.cloudy yellowcloudy yellowclear yellowclear yellowclear colorlessclear colorlesswhite solidwhite solidCHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•General ProceduresGeneral ProceduresA centrifuge is used to separate heavier A centrifuge is used to separate heavier material, the solid precipitate, from the lighter material, the solid precipitate, from the lighter liquid material by using centripetal force. liquid material by using centripetal force. Exercise caution when using the centrifuge. Exercise caution when using the centrifuge. Use a counterbalance micro test tubeUse a counterbalance micro test tube..samplesamplecounterbalancecounterbalanceCHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group IUse a water bath to heat all Use a water bath to heat all mixtures.mixtures.•General ProceduresGeneral ProceduresPay attention to whether you are to keep Pay attention to whether you are to keep or discard the or discard the precipitateprecipitate and/or and/or supernatantsupernatant..supernatantsupernatantprecipitateprecipitateCHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•Prepare a Known Prepare a Known solution (you can label solution (you can label the test tube “K”) by the test tube “K”) by adding 8 drops each of:adding 8 drops each of:AgNOAgNO3Pb(NOPb(NO33))22HgHg22(NO(NO33))22CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•Prepare an Unknown Prepare an Unknown solution (you can label solution (you can label the test tube “U”) by the test tube “U”) by adding 15 drops of your adding 15 drops of your assigned unknown assigned unknown mixture.mixture.CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•Add HCl to both your known and Add HCl to both your known and unknown solutions and stir well with unknown solutions and stir well with a clean and dry micro stirring rod.a clean and dry micro stirring rod.•AgAg++(aq)(aq), Pb, Pb2+2+(aq)(aq), and Hg, and Hg222+2+(aq)(aq), ions all , ions all form white precipitates with Cl form white precipitates with Cl -- at at room temperature:room temperature:AgClAgCl(s), PbCl, PbCl2(s), Hg Hg22ClCl2(s)•Now you have a mixture of all 3 Now you have a mixture of all 3 white precipitates in the test tube. white precipitates in the test tube. The following steps will illustrate how The following steps will illustrate how to separate all 3 of ions, silver(I), to separate all 3 of ions, silver(I), lead(II) and mercury(I), from each lead(II) and mercury(I), from each other and how to positively identify other and how to positively identify them in your unknown mixture.them in your unknown mixture.CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•Place the test tubes in the Place the test tubes in the centrifuge so that they counter centrifuge so that they counter balance one another.balance one another.•After centrifuging the solution for After centrifuging the solution for 30 seconds, the solid precipitate 30 seconds, the solid precipitate will fall to the bottom of the test will fall to the bottom of the test tube.tube.CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative Analysis: Group I•The supernatant, the liquid The supernatant, the liquid above the solid precipitate, can above the solid precipitate, can be removed by decanting, be removed by decanting, pouring off the liquid, or by using pouring off the liquid, or by using a disposable transfer pipet. a disposable transfer pipet. •Read the instructions carefully Read the instructions carefully for each step to determine if the for each step to determine if the supernatant should be saved supernatant should be saved into a new clean and dry test into a new clean and dry test tube, or can be discarded into tube, or can be discarded into the sink (or waste bottle). the sink (or waste bottle).CHM 101/102CHM 101/102Laboratory ManualLaboratory ManualLaboratory ManualQualitative Analysis: Group IQualitative