Question

Copper and brass vessels are cleaned with lemon

Answer 1

citric acid in lemon etctes away copper oxide that give rhe vessel a dark color copper became dirtythey have formed the layer of copperoxide on their surface.c ooper oxide is a weak base and consequentlyreact with a weak acid such as lemon

Answer 2

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Ans: The citric acid present in the lemon or tamarind neutralises 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 lustre.