Question

What is dissolution and how does this result in weathering?

Answer 1

Removal of some minerals (e.g. calcium carbonate) and corrosion of rocks.

Explanation:

When rocks are exposed to the external environment the minerals of which they are composed undergo to chemical attack by several agents. The most common is the chemical dissolution of soluble minerals, such as calcium carbonate, by acidic solutions.

The carbon dioxide present in the atmosphere is dissolved in the rainwater which becomes acidic. Once this acidic water impacts calcareous rocks (limestone) the calcium carbonate, `"CaCO"_3`, which is their major component is transformed in calcium bicarbonate, `"Ca"("HCO"_3)_2`, soluble in water and thus removed from the rock. The resulting is the progressive erosion of the rock.This process is called weathering.

There is a number of minerals that can be dissolved by chemical agents naturally present in the environment and this leads to the progressive erosion of the landscape.