Question

A copper coin was kept dipped in silver nitrate solution for few hours. what will happen to copper coin and the color of solution

Answer 1

Copper metal is more reactive than silver metal thus, when copper coin is kept immersed in silver nitrate solution for some time, it displaces silver from silver nitrate solution.
The grey solid crystal of Ag metal are seen growing on the copper coin and solution turns blue in colour.

Answer 2

when copper coin was kept dipped in silver nitrate solution for few hours. then copper being more reactive than silver displaces the silver from silver nitrate and form copper nitrate solution.  the color of solution is blue.