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NTA Abhyas JEE Main2020Chemistryd and f Block ElementsPractice

Copper becomes green when exposed to moist air for a long period. This is due to :

Options

  1. AThe formation of a layer of cupric hydroxide on the surface of copper.
  2. BThe formation of a layer of basic carbonate of copper on the surface of copper.
  3. CThe formation of basic copper sulphate layer on the surface of the metal.
  4. DThe formation of a layer of cupric oxide on the surface of copper.

Correct answer

B. The formation of a layer of basic carbonate of copper on the surface of copper.

Step-by-step solution

Due to formation of Basic copper carbonate CuCO 3 .Cu(OH) 2 in atmosphere.

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