Answer:
the surface area of the rock is increased, which allows a greater amount of chemical weathering to occur.
Explanation:
Mechanical weathering is the physical disintegration of rocks into smaller bits. The smaller pieces of rocks makes the action of chemical weathering faster and easier. A massive and intact lump of rock would be very difficult to be chemically decomposed compared to smaller fragments and chunks of rocks.
From chemical kinetics, the larger the surface area the faster the reaction becomes. For the same mass of a solid substance, granules and powder, the reaction rate of the powder is the fastest followed by the granules. This is exactly what physical weathering tends to achieve. Physical disintegration of rocks would decrease the sizes of rocks and provide a larger surface area for the action of chemical agents.
