ZnO shows yellow colour on heating due toA. Frenkel defectB. Metal excess defectC. Metal deficiency defectD. Schottky defect.

ZnO shows yellow colour on heating due toA. Frenkel defectB. Metal exc

1.	ZnO shows yellow colour on heating due toA. Frenkel defectB. Metal excess defectC. Metal deficiency defectD. Schottky defect.
Answer» Correct Answer - B Zinc oxide is white in colour at room temperature. On heating it loses oxygen and turns yellow. `ZnOoverset("Heating")rarrZn^(2+)+(1)/(2)O_(2)+2e^(-)` Now there is excess of zinc in the crystal and its formula becomes `Zn_(1+x)O`. The excess `Zn^(2+)` ions move to interstitial sites and the electrons to neighbouring interstitial sites.

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ZnO shows yellow colour on heating due toA. Frenkel defectB. Metal excess defectC. Metal deficiency defectD. Schottky defect.

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