Weathered rocks on the shore dissolve into the sea.
Weathering is a general term that describes the surface processes that breakdown and change rocks and minerals on the Earth. Chemical weathering occurs when the composition of a rock or mineral is changed. Water is most commonly responsible for the initiation of chemical weathering, which occurs more readily with smaller fragments of rocks or minerals. Smaller fragments translate to more available surface area to be affected by one of the multiple processes that lead to chemical weathering.
Hydration
In arid environments where there are many salts, hydration is a common chemical weathering process. During hydration H+ and OH- ions typically attach to a reacted compound, which changes the atomic structure of the weathered material. Additionally, rocks and minerals absorb water and may expand.
Hydrolysis
Often confused with hydration, hydrolysis is a chemical weathering process that occurs when water molecules react with a rock or mineral to produce a new compound. Specifically, the H+ and OH- ions react and increase the acidity of the solution through the release of hydroxide ions.
Oxydation/Reduction
Oxidation is the weathering process that occurs when oxygen from water or the atmosphere reacts with a rock or mineral. The rock or mineral becomes an oxide because of the loss of one or more electrons during the reaction. Common oxides include aluminum and iron oxides, which can be identified by their yellowish and reddish tones. Reduction is the exact opposite reaction of oxidation.
Dissolution
When rocks and minerals have been weathered to extremely small fragments, dissolution often occurs. Dissolution is the chemical weathering process where rocks and minerals are dissolved into water, Earth's most plentiful and effective solvent. Typically the solution is carried away and may leave holes in rocks and minerals. This is also the process that is responsible for the formation of caves in limestone.
Tags: rocks minerals, chemical weathering, rock mineral, weathering process, chemical weathering process