Question

Which of these actions is an example of chemical weathering

A. Freezing water widens the cracks in rocks
B. Plants roots force their way into cracks in rocks and break them
C. Oxygen in air reacts with iron content in rocks, causing them to change color
D. Strong winds peel soft rock away, leaving harder rock behind

Answer 1

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

Answer 2

The correct answer is option C.

Explanation:

The erosion or the disintegrations of the building material or rock by the chemical reactions instead of a mechanical process termed as chemical weathering. Oxygen present in the air reacts with iron content present in rocks, causing them to react with oxygen in the air and form an iron oxide that can leach in rock and make it rusty looking. This change in color is completely a chemical change that is occurring. There is also the erosion of rock that takes place in this process.

Thus, the correct answer is option C.