Question

Why is a copper roof turning green a chemical change?​

Answer 1

Copper will start to react with the oxygen in the air to form copper oxide. The copper oxide will continue reacting to oxygen over time. As the copper oxide continues to react with carbon dioxide and water in the air it coats the surface with that iconic blue-green patina colour

Answer 2

The color change of a copper roof turning green is a chemical change because it involves a chemical reaction. Copper reacts with oxygen and other compounds in the environment to form compounds such as copper sulfate and copper oxide, which have a green color.

Step-by-step explanation:

The color change of a copper roof turning green is a chemical change because it involves a chemical reaction. Copper reacts with oxygen and other compounds in the environment to form compounds such as copper sulfate and copper oxide, which have a green color. The formation of these compounds is a result of chemical reactions, where the copper undergoes oxidation and forms new substances.