Question

why does a copper vessel has a green coating?

Answer 1

Copper metal when exposed to air turns green in colour due to corrosion. When copper vessel isexposed to air in rainy season, the metal reacts with gases and moisture and atmospheric gases to form a mixture of coppercarbonate and copper hydroxide. This gives a green colour to the surface of copper metal

Answer 2

copper vessel has a green coating so as it reacts with moisture n air so to prevent it from corrosion... green coating is done