Question

7. A student has been collecting silver and copper coins. One day she observed a black
coating on silver coin and green coating on copper coins. Which chemical phenomenon is
responsible for these coatings. Write the chemical names of black and green coatings
with their chemical formula
How can you prevent this process on iron metal?​

Answer 1

Answer:

Here is your answer.

Explanation:

Black coating on silver coin is due to silver sulphide. (Ag2s)

And

Green coating on gold coin is due to copper carbonate and copper hydroxide.

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