What process involves a chemical change in rock-forming minerals?

The process that involves a chemical change in rock-forming minerals is chemical weathering. This process occurs when minerals in rocks interact with various environmental factors, such as water, oxygen, acids, and biological organisms, leading to chemical reactions that alter the composition of the minerals.

For instance, when feldspar minerals in granite react with carbonic acid from rainwater, they can be transformed into clay minerals through hydrolysis. This alteration not only changes the minerals themselves but can also affect the physical structure of the rock over time, leading to its breakdown and the formation of soil.

Chemical weathering is significant because it plays a crucial role in shaping landscapes, influencing soil formation, and cycling essential nutrients in ecosystems. It is distinct from physical and mechanical weathering, which involve the physical breakdown of rocks without altering their chemical composition. Erosion, on the other hand, refers to the movement of weathered material rather than the chemical changes that cause the material to break down.