Absorption (chemistry)

Absorption is a physical or chemical phenomenon or a process in which atoms, molecules or ions enter the liquid or solid bulk phase of a material.

A more common definition is that "Absorption is a chemical or physical phenomenon in which the molecules, atoms and ions of the substance getting absorbed enter into the bulk phase (gas, liquid or solid) of the material in which it is taken up."

A more general term is sorption, which covers absorption, adsorption, and ion exchange.

The process of gas or liquid which penetrate into the body of adsorbent is commonly known as absorption.

The water can be driven off by heating in an oven, leading to a measurable decrease in weight, which will gradually be regained if the fiber is returned to a 'normal' atmosphere.

This effect is crucial in the textile industry – where the proportion of a material's weight made up by water is called the moisture regain.