Which of the following would dissolve in warm dilute H2SO4 without effervescence, to give a blue solution?
-
Copper turnings
- Copper (ll) trioxocarbonate (IV)
- Copper (ll) oxide
- Copper alloy
The correct answer is: A
Explanation
Copper turnings will dissolve in warm dilute sulfuric acid (H2SO4) without effervescence to give a blue solution.
When copper reacts with sulfuric acid, it forms copper sulfate (CuSO4), a salt that is blue in color. The reaction is:
- Cu (s) + H2SO4 (aq) → CuSO4 (aq) + H2 (g) ↑
- Copper + Sulfuric acid → Copper sulfate + Hydrogen