Question

Write the defect of non-stoichiometric compound.

Answer 1

These defects are of two types:

(a) Metal Excess Defect and (b) Metal Deficiency Defect. Metal excess defect due to the presence of extra cations at interstitial sites: In this case, there are extra positive ions occupying interstitial sites and the electrons in another interstitial sites to maintain electrical neutrality. The defect may be visualised as the loss of non-metal atoms which leave their electrons behind. The excess metal ions occupy interstitial positions.