Question

1. What happens when copper vessel is exposed to
moist air for a long time?​

Answer 1

Answer:

Green colour is obtained.

Explanation:

When a copper vessel is exposed to moist air for a long time it develops a Green layer on its surface. 

Copper corrodes by oxidation in which it reacts with oxygen in the air to form copper oxide.

 Copper oxide then combines with Carbon dioxide to make copper-carbonate, which gives it a green colour.

Answer 2

Explanation:

Copper becomes green when exposed to moist air for a long period. This is due to

When a copper vessel is exposed to moist air for a long time it develops a green layer on its surface. Copper corrodes by oxidation in which it reacts with oxygen in the air to form copper oxide.

Copper oxide then combines with carbon dioxide to make copper carbonate, which gives it a green colour. This process is called corrosion of copper.

The green material is a mixture of copper hydroxide (Cu(OH)2) and copper carbonate (CuCO3). The following is the reaction:

2Cu(s)+H

2

O(g)+CO

2

+O

2

→Cu(OH)

2

+CuCO

3

(s)

Copper(II) carbonate is a blue-green compound.