One key factor in the rate of chemical weathering is the size of the rocks. The rate of chemical weathering like other chemical reaction depends on the size of the rocks.
Chemical weathering is the decomposition and decay of rocks.
In chemical weathering, a rock unit undergoes a chemical change.
For an effective chemical weathering of a rock, physical disintegration of a rock piece must have occurred first.
The surface area exposed proportionally affects the rate of chemical weathering.
Smaller chunks of rocks have a large surface area and they are weathered faster.