Zinc oxide is white, on heating it becomes yellow Explain - Chemistry -

Question

Zinc oxide is white, on heating it becomes yellow Explain

Neelam Yadav · Accepted Answer

Zinc oxide is an example of non stoichiometric defect under the
category metal excess defect (excess cations occupying the
interstitial site) In ZnO, Zn2+ ions occupy the
interstitial sites and electrons are trapped in the interstitial
sites for the neutralization Crystals that shows such type of
defects are generally colored
Zinc oxide is white in color but on heating it turns into yellow
because on heating it loses oxygen reversibly at high
temperature
The reaction is as under:-
ZnO â†’ Zn2+ + 1/2 O2 +
2e-

Zinc oxide is white, on heating it becomes yellow. Explain.