How is physical weathering different from chemical weathering?

Physical weathering, also known as mechanical weathering, refers to the processes that break down rocks into smaller fragments without changing their chemical composition. It involves the physical disintegration or breakdown of rocks into smaller pieces, but it does not alter the mineral composition or chemical structure of the rocks.

In contrast, chemical weathering involves the chemical alteration or decomposition of rocks and minerals through various chemical reactions. It occurs when rocks come into contact with water, air, acids, or other chemicals that cause the minerals in the rocks to undergo chemical changes. Chemical weathering can result in the dissolution of minerals, the formation of new minerals, or the breakdown of rocks into new substances.

While physical weathering mainly involves the physical breakup of rocks through processes like frost wedging, thermal expansion, or abrasion, chemical weathering involves the chemical reactions that can dissolve, alter, or break down the minerals present in rocks. Both physical and chemical weathering often work together to break down rocks and contribute to the overall process of weathering.

Choices are

 A. In physical weathering, the composition of the weather substance is changed.
 A. In physical weathering, the composition of the weather substance is changed.

 B. Physical weathering is always faster than chemical weathering.
 B. Physical weathering is always faster than chemical weathering.

 C. In chemical weathering, the composition of the weathered substance is changed.
 C. In chemical weathering, the composition of the weathered substance is changed.

 D. Chemical weathering is always faster than physical weathering.