Question

question 3
which is a chemical property of copper?
○ is a solid at room temperature
○ has a boiling point of 2567 °c
○ can be stretched into wire
○ reacts in air to form a green layer

Explanation:

A chemical property describes a substance's ability to undergo a chemical change or reaction. The first three options are physical properties (state, boiling point, malleability) that do not involve a change in chemical composition. The formation of a green layer (patina) is a chemical reaction between copper, oxygen, water, and carbon dioxide in air, which alters copper's chemical structure.

Answer:

reacts in air to form a green layer