Question

An electron trapped in an anion site in a crystal is called

Answer 1

F-centres

Explanation:

• An electron trapped in an anion site in a crystal is called F-cenres.
• An F-center is a crystallographic defect in which one or more unpaired electrons occupy an anionic vacancy in a crystal. Because electrons in such a vacancy absorb light in the visible spectrum, a normally clear material turns coloured.
• F centres are created by heating a crystal in excess of an alkali vapour or irradiating it with X rays.
• NaCl is an excellent example of a crystal with F centres.