The Earth Contents

3. Weathering

Dissolution by water weathers minerals such as gypsum and sodium chloride

Dissolution is the simplest of all weathering reactions. The polar nature of water makes it very effective at dissolving ionic-bonded solids because it enables water to envelope both positive and negative ions. Hence oppositely charged species can be kept apart in solution, with the water layers shielding differently charged ions from each other. However, most rock-forming minerals are silicates, which are mainly covalently bonded and which are therefore only poorly reactive towards pure water. Simple dissolution is important for only a few minerals such as gypsum and sodium chloride (common table salt).

Dissolution by water weathers minerals.

Explain dissolution.