How does the mechanical weathering (from wind) of a rock enhance the chemical weathering (by rain) of the rock?

Weathering is the process by which rocks are broken down into smaller fragments. These weathered components may then be transported to different locations by the processes or erosion. Weathering can be classified as either mechanical or chemical, depending on whether physical forces are acting or chemical reactions are taking place, respectively.

Mechanical weathering can be caused by physical agents such as wind, frost, temperature, and abrasion. Chemical weathering can be caused by process such as hydrolysis, oxidation, and dissolution. These weathering processes also assist each other. For example, chemical reactions are more wide spread if more surface area is available for weathering. This can be made possible by mechanical weathering. If forces such as wind cause abrasions on a rock's surface and expose it more to other weathering agents, such as rain, hydrolysis (a process of chemical weathering) will take place over a larger surface area and a higher rate of weathering will be accomplished. 

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