1. If a solution of hydrochloric acid is added to a solution of sodium carbonate, what is observed? Write the net ionic equation of any reaction that may occur (4P). 2. You have a clear colorless unknown solution with a group I cation. After adding some hydrochloric acid solution you obtain a white precipitate. Addition of ammonia causes the white precipitate to dissolve. Acidifying with nitric acid makes the precipitate reappear. Which cation do you suggest was in the unknown sample? Write the net ionic equation of any reaction that may occur (4P). 3. When testing for the presence of sulfate, what reagent is added to the solution? What final result indicates the presence of sulfate? Write the net ionic equation of any reaction that may occur (4P).