Q: What compound gives tarnished copper it's green color?


Read this paragraph and choose the correct option from the provided answers:

A: The copper has become tarnished. The tarnish—also called patina—is a compound called copper carbonate, which is green. Copper carbonate forms when copper undergoes a chemical reaction with carbon dioxide in moist air. The green patina that forms on copper actually preserves the underlying metal. That’s why it’s not removed from the statue. Some people also think that the patina looks attractive.

 Choices:

- bronze

- zinc

- brass

- copper carbonate


A:
copper carbonate