The purpose of this lab was to determine which combinations of ions form water-insoluble precipitates. .
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II. Materials .
1 pair of safety goggles .
1 plastic wash bottle with distilled water .
1 wash bucket .
soap .
5 test tubes .
water .
Chemicals: .
Set 1 .
0.1M barium nitrate, Ba(NO3)2 .
0.1M sodium sulfate, Na2SO4 .
0.1M aluminum sulfate, Al2(SO4)3 .
0.1M magnesium nitrate, Mg(NO3)2 .
0.1M magnesium chloride, MgCl2 .
0.1M aluminum chloride AlCl3 .
Set 2 .
0.1M potassium chloride, KCl .
0.1M magnesium chloride, MgCl2 .
0.1M sodium sulfate, Na2SO4 .
0.2M sodium hydroxide, NaOH .
0.1M barium chloride, BaCl2 .
0.1M magnesium sulfate, MgSO4 .
Set 3 .
0.1M barium chloride, BaCl2 .
0.1M magnesium nitrate, Mg(NO3)2 .
0.2M sodium chromate, Na2CrO4 .
0.1M aluminum sulfate, Al2(SO4)3 .
0.2M potassium chromate, K2CrO4 .
0.2M silver nitrate, AgNO3 .
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III. Procedure .
1. Put on safety goggles. Then obtain a number of small test tubes and a set of chemicals in dropper bottles. .
2. Using data table 1 as a guide, mix every possible pair of solutions in a set in a separate test tube. Use about a milliliter of each solution. Do not contaminate the individual droppers with different solutions. Be sure to wash out your test tubes before and after each use. Flick the test tube to mix the solutions. Observe each mixture carefully for signs of a precipitate. (Some precipitates are light in color and may be hard to see.) Note the color of any precipitate formed.
