A numismatist (coin collector) has been collecting gold coins, silver coins and copper coins for a long time. One day he observed a black coating on silver coins and green coating on copper coins. What chemical process is responsible for these coatings. Also name the chemical formula of the black and green coatings

Open in App

Solution

The phenomena responsible for the formation of a coating on copper and silver coins is known as corrosion. Silver turns black due to the formation of silver sulphide (Ag₂S) while copper turns green due to the formation of a mixture of copper carbonate and copper hydroxide [(CuCO₃). Cu(OH)₂].

Suggest Corrections

Similar questions

A numismatist (coin collector) has been collecting gold coins, silver coins and copper coins for a long time. One day he observed a black coating on silver coins and green coating on copper coins. Which chemical process is responsible for these coatings?

Q. Rahul has been collecting copper coins and silver coins. One day he observed a green coating on copper coins and a black coating on silver coins. State the chemical phenomenon responsible for these coatings and also write chemical names of each coating.

Q. Reena has been collecting silver coins and copper coins. One day, she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.

Q. A box contains