Question

ZnO shows yellow colour on Heating due to:

• A. d-d transition
• B. C-T spectra
• C. Higher polarisation caused by $Z{n}^{2+}$ ion
• D. F-centres

Answer 1

The correct option is D F-centres

$ZnO$ shows yellow colour of heating due to F-centre

$ZnO⟶Z{n}^{2+}+2e^{-}+\frac{1}{2}{O}_2$

Electron get trapped in anion sites. This is called as F-centre. Due to F-centre colour of many compounds occurs.