• Metal excess defect due to the presence of extra cations at interstitial sites:

• When white zinc oxide is heated, it loses oxygen and turns yellow.

Then, zinc becomes excess in the crystal, leading the formula of the oxide to. The excess Zn²⁺ions move to the interstitial sites, and the electrons move to the neighbouring interstitial sites.

what is meant by??

In these type of defects, extra cations are present at the interstitial positions in the lattice. To maintain the electrical neutrality, extra electrons are present at the interstitial positions. These type of defects are shown by compounds such as ZnO, CdO, etc. When white zinc oxide is heated, it loses oxygen and turns yellow.

Then, zinc becomes excess in the crystal, leading the formula of the oxide to. The excess Zn²⁺ ions move to the interstitial sites, and the electrons move to the neighbouring interstitial sites.