Q57 / 180 · AIIMS 2018 (26 May) · Chemistry

What colour is observed when $\mathrm{ZnO}$ is heated?

Correct answer
A
Yellow
B
Violet
C
Green
D
Blue

Solution

Zinc oxide is white in colour at room temperature. On heating it loses oxygen and turns yellow.

Hence, the correct answer is option: 'A'.

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