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JEE Main2014Chemistryd and f Block ElementsActual

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 oxide 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 a layer of cupric hydroxide on the surface of copper.
  4. Dthe formation of basic copper sulphate layer on the surface of the metal.

Correct answer

D. the formation of basic copper sulphate layer on the surface of the metal.

Step-by-step solution

Copper when exposed to moist air having CO ₂ . It gets superficially coated with a green layer of basic carbonate CuCO ₃ . Cu ( OH )₂ .

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