Compare chemical weathering to mechanical weathering

It affects the rocks in place and no transport is involved. This distinguishes weathering from erosion. Mechanical / physical weathering - physical disintegration of a rock into smaller fragments, each with the same properties as the original. Occurs mainly by temperature and pressure changes

Chemical weathering is the process by which the internal structure of a mineral is altered by the addition or removal of elements, while mechanical weathering is the breaking down of big rocks to small rocks.