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Maharashtra State BoardSSC (English Medium) 10th Standard

Write scientific reason. Lemon or tamarind is used for cleaning copper vessels turned greenish.

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Question

Write scientific reasons.

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

Short/Brief Note
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Solution

  1. Copper vessels turned greenish due to the formation of copper carbonate layer.
  2. The citric acid present in the lemon or tamarind neutralizes the basic copper carbonate and dissolves the layer.
  3. That is why tarnished copper vessels are cleaned with lemon or tamarind juice to give the surface of the copper vessel its characteristic lustre.
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Chapter 8: Metallurgy - Exercise [Page 109]

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