Physical weathering is a term used in science that refers to the geological process of rocks breaking apart without changing their chemical composition. Over time, movements of the Earth and environment can break apart rock formations, causing physical weathering.
Chemical weathering occurs when there are changes in the chemical compositions of the rock or minerals from exposure to the environment. Chemical weathering includes chemical changes that may decompose, dissolve or break down various parts of the rock or other landform. These changes are a result of other minerals and chemicals that seep into rocks, usually in rain water or as gases. Acid rain is a prime cause of chemical weathering.
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