MCQ : The green patches that form on the surface of copper is

Question

The green patches that form on the surface of copper is –

1. CuSO₄
2. Cu(OH)₂
3. CuO
4. CuSO₄.3Cu(OH)₂

Answer

(d) CuSO₄.3Cu(OH)₂

Explanation:

The green patches formed on the surface of copper are due to the formation of copper carbonate (CuCO₃) or copper hydroxide (Cu(OH)₂), which are the result of the reaction of copper metal with atmospheric carbon dioxide and moisture.