Q. Activated Charcoal is used to remove colouring matter from pure substances by:
Answer: Adsorption
Notes: Heating wood to a very high temperature in the absence of air makes charcoal. When it is heated to an even higher temperature, about 930°C, impurities are driven from its surface and it becomes activated charcoal, sometimes called decolorizing charcoal. This activated charcoal because of adhesion can remove impurities in either the gaseous or liquid state from many solutions.