Question

Lemon or tamarind is used for cleaning copper vessel turned greenish.

Comment on the above statement.

Answer 1

1) Copper reacts with carbon dioxide in the air to form copper carbonate.

2) As a result, copper loses its shiny brown surface forming a green layer of copper carbonate.

3) The citric acid present in the lemon or tamarind neutralizes the basis copper carbonate and dissolves the layer.

4) Therefore, tarnished copper vessels are cleaned with lemon or tamarind juice to give luster to the surface of the copper vessel.