The Separation of Tin, Cobalt, Nickel and Calcium Zelda Tackey, Hayley Field, Susan Clark and Karlyn East March 17,2011

Overview of the Experiment This experiment was developed to see if the ions tin, cobalt, nickel and calcium could be individually and properly precipitated out from the mixture that were made with these ions.

Introduction and Hypothesis All the ions presented will be properly separated (will precipitate) out of the mixture of nickel, tin, cobalt and calcium provided.

Reactants and Materials Reactants Needed: tin (which was later replaced with lithium) cobalt calcium sodium sulfate sodium hydroxide calcium carbonate sodium phosphate Materials: Ions (Reactants) Needed Test Tubes Bunsen Burner Striker Test Tube Rack Centrifuge

Procedure 1. Get a mixture of Ni 2+, Sn 2+ (later changed to Li 1+ ),Co 2+,Ca Add sodium sulfate to precipitate Ca 2+ 3.Calcium sulfate is formed by performing the previous step 4. To separate the remaining liquid from the precipitant, take the test tube and pour the remaining liquid into another test tube. 5. Add sodium phosphate to the CO 2+ Cobaltous phosphate will be formed by this step 6. To precipitate lithium, a flame test must be preformed. The flame should burn a deep red color 7. Add sodium carbonate to the mixture to obtain Ni 2+. Nickel carbonate will be left after this step is performed

Observations When sodium sulfate was added to the mixture, nothing appeared to happen. The test tubes were placed in ice for awhile and nothing occurred. A much stronger solution had to be made to see if any ions could be precipitated out. When sodium phosphate was added to the mixture in a test tube and once again nothing appeared to happen. After letting it sit for some time, nothing occurred When sodium carbonate was added to the mixture in a test tube it turned a purplish color and was cloudy. A substance formed at the bottom. After placing the test tube in the centrifuge the liquid left behind was poured into another test tube. The substance left behind a purple powder, which was nickel and cobalt.

Observations (cont.) Cobalt-sodium phosphate is added to the mixture at a much higher concentration Calcium-When sodium sulfate was added and the mixture sat for a couple of days (the weekend) a grainy, salt-looking substance formed at the bottom of the tube Cobalt (cont.)-Sodium carbonate precipitates out cobalt and nickel. This required cobalt to be precipitated out separately. When carbonate was added it turned a purplish-pink color. This caused cobalt to separate out without interference.

Observations (cont.) Lithium- A wood splint was dipped in the mixture of lithium and nickel. When place over the flame of the burner, the lithium could be seen because it gave off a deep red color.

Analysis

Analysis cont.

Conclusion The experiment was not as successful as planned. Many of the ions did not precipitate out like they were originally planned to. It was discovered that sodium carbonate could precipitates out cobalt and nickel and this interference could have been the reason why nothing occurred in the beginning of the experiment. Despite the few challenges, other means of precipitating the ions were found.