[Truthiness]

Hello, I'm having some trouble with a couple of questions:

1) Silver nitrate is added to a solution and a precipitate forms. This precipitate dissolves when concentrated ammonia is added. What anion was present in the original solution?
I've gotten as far as figuring out all nitrates are soluble so the precipitate is with silver.

2) You have an aqueous blue solution. Addition of dilute hydrochloric acid produces a pecipitate. The precipitate dissolves when the solution is heated to boiling. What two cations were in the original solution?

All help is greatly appreciated.

[Alberto_Kravina]

Try to solve it yourself- we're not here to do your homework-

Hint: This insoluble silver salts were/are used in photography because they're instable when exposed to light- if this salts are exposed to light elementar silver and the corresponding halogen forms.

2) You have an aqueous blue solution. Addition of dilute hydrochloric acid produces a pecipitate. The precipitate dissolves when the solution is heated to boiling. What two cations were in the original solution?

interesting- normally a blue solution could be Cu²⁺, but it doesn't form a ppt with HCl...

as I said- try to solve it by yourself (I answered your first question "indirectly". )