Question

Which of these actions is an example of chemical weathering

Answer 1

C. is an example of chemical weathering.

The interaction between oxygen and iron is a chemical change, while the other options describe changes that only happen physically. (Ice creates cracks by force, not by changing what the rock is made from, and so on.)

Answer 2

C. Oxygen reacts with iron content in rocks, causing them to change color.

Any time you have a chemical change, that means that one substance becomes and entirely new substance, such as iron becoming rust. In a physical change, such as a substance cracking or breaking, it is still made out of the original substance, no new substance is formed.