1. Group 1 Chemical #1 Copper Sulfate CuSO 4 *The copper sulfate is in a solution of water Chemical #2 Ammonia NH 3 *The ammonia is in a solution of water

2. Group 2 Chemical #1 Zinc Zn Chemical #2 Hydrochloric Acid HCl *The hydrochloric acid is in a solution of water

3. Group 3 Chemical #1 Milk *Milk is a complex mixture of fats, carbohydrates, and proteins. It does not have a specific chemical formula, but the part of the milk that is reacting is a protein called casein. Chemical #2 Acetic Acid C 2 H 4 O 2 *The acetic acid is in a solution of water

4. Group 4 Chemical #1 Sodium Bicarbonate NaHCO 3 Chemical #2 Acetic Acid C 2 H 4 O 2 *The acetic acid is in a solution of water

5. Group 5 Chemical #1 Lead Nitrate Pb(NO 3 ) 2 *The lead nitrate is in a solution of water Chemical #2 Sodium Chloride NaCl *The sodium chloride is in a solution of water

6. Group 6 Chemical #1 Sodium Bicarbonate NaHCO 3 *Both chemicals are in the tablet. The tablet is added to water to start the reaction. Chemical #2 Citric Acid C 6 H 8 O 7 *Both chemicals are in the tablet. The tablet is added to water to start the reaction.

7. Group 7 Chemical #1 Starch C 6 H 10 O 5 *The starch is in a solution of water Chemical #2 Iodine I * The iodine is in a solution of ethyl alcohol. An alcohol solution is called a “tincture”

8. Group 8 Chemical #1 Steel Wool Fe *There are other elements, like carbon, present in steel wool. Iron is the element that reacts with vinegar in this case Chemical #2 Acetic Acid C 2 H 4 O 2 *The acetic acid is in a solution of water