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Assertion: ZnO becomes yellow when it is...

Assertion: `ZnO` becomes yellow when it is heated.
Reason: The anionic sites occupied by unpared electrons (due to F_centres)

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reson are true but reason is not the correct explanation of assertion.

C

if assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A
Zinc oxides white in oclour at room temperature. On heating it loses oxygen and turns yellow
`ZnO overset("heating")toZn^(2+)+(1)/(2)O_(2)+2e^(-)`
(metal deficiency effect due to presence of extra cations at interstitial sites)
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