Which type of chemical weathering involves the direct addition of water molecules to the mineral structure, causing expansion and mechanical disintegration?

💡 Solution & Explanation

Hydration is a chemical weathering process where water molecules are directly incorporated into the crystal structure of minerals, causing them to expand and generate internal mechanical stresses that break down rocks. This differs from hydrolysis where water chemically reacts with minerals to form new compounds. Hydration is particularly effective in transforming anhydrous minerals like anhydrite into gypsum.