Here's why:
* Physical weathering involves mechanical forces that break down rocks into smaller pieces without changing their chemical makeup. Examples include:
* Frost wedging: Water freezes in cracks and expands, putting pressure on the rock.
* Abrasion: Rocks rub against each other, wearing them down.
* Thermal stress: Repeated heating and cooling causes rocks to expand and contract, weakening them.
* Chemical weathering involves chemical reactions that change the composition of rocks and minerals. This results in new minerals and substances. Examples include:
* Oxidation: Reactions with oxygen, like rusting.
* Dissolution: Rocks dissolving in water.
* Hydrolysis: Reactions with water, breaking down minerals.
Since the question asks for the breakdown without a change in composition, the answer is physical weathering.
