Copper vessels left for a long time in moist air develop a dull green coating. The coating is mainly

copper sulphateCorrect answerYour answercopper oxideCorrect answerYour answerbasic copper carbonateCorrect answerYour answercopper chlorideCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Copper reacts slowly with moist carbon dioxide and oxygen in the air.
The green film formed is basic copper carbonate, a mixture of copper carbonate and copper hydroxide. This is corrosion of copper.

Worth noting

Copper oxide is black, not green; it forms when copper is heated in dry air.

Concept: Corrosion of copper
Typical timeTypical: 90 s
Your timeYours: —

The rule this testsChemical reactions

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Copper vessels left for a long time in moist air develop a dull green coating. The coating is mainly

Explanation