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Metals and Non-metals
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05/09/2021 6:18 pm
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You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
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05/09/2021 6:19 pm
Copper metal slowly reacts with water, carbon dioxide and oxygen present in air to form a layer of basic copper carbonate which is greenish in colour. This layer slowly gets deposited on the surface of the metal.
Now lemon juice contains citric acid while tartaric acid is present in tamarind. Both these acids react with basic copper carbonate to form soluble salts such as copper acetate (with citric acid) and copper tartrate (with tartaric acid). The equations for the reactions are complicated and are not given. These salts gets removed from the surface of the copper metal and the surface of the metal shines.
This post was modified 4 years ago by Shivani siva