हिंदी

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

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प्रश्न

Write scientific reasons.

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

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उत्तर

  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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अध्याय 8: Metallurgy - Exercise [पृष्ठ १०९]

संबंधित प्रश्न

Give reasons:

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Explain why, iron sheets are coated with zinc.


The corrosion of iron is called ______.


Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.


Name any two metals which do not corrode easily.


Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.


A common metal which is highly resistant to corrosion is ______.


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  1. Name the metals X and Y.
  2. Which of the two metals is more reactive: X or Y?
  3. Name one ore or metal X. Also write its chemical formula.
  4. Name one ore of metal Y. Also write its chemical formula.
  5. Name one alloy of metal X and one alloy of metal Y.

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In ______ process a layer of molten tin is deposited on metals.


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