Question 5.
Write scientific reason.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
Answer:
Copper reacts with moist carbon dioxide in the air to form copper carbonate. The citric acid present in the lemon or tamarind neutralizes the basis copper carbonate and dissolves the layer. That is why tarnished copper vessels are cleaned with lemon or tamarind juice to give the surface of the copper vessel its characteristic shiny appearance.