Final answer:
Oxidation is not a physical weathering process; it is a chemical weathering process. Physical weathering includes processes that physically break down rocks without altering their chemical composition, unlike oxidation, which involves chemical changes.
Step-by-step explanation:
The process that is NOT considered to be physical weathering among the options provided is oxidation. Oxidation is a chemical weathering process, which involves the chemical reaction of oxygen with other substances. In contrast, physical weathering, also known as mechanical weathering, includes processes like near-surface fracturing, frost wedging, and prying by plant roots that break down rocks and minerals through physical forces without changing their chemical composition.
Chemical weathering happens when chemical reactions, such as hydration, hydrolysis, carbonation, and oxidation, alter the internal structures of minerals causing their breakdown. These reactions often lead to the formation of new substances. For example, the oxidation of iron in rocks can lead to the formation of rust (iron oxide), which weakens the rock structure. This is different from the examples of physical weathering, which primarily involve the breaking apart or disintegration of rock without chemical alteration.