Question

The colour of the residue when${\mathrm{PbO}}_2$ decomposes to$\mathrm{PbO}\mathrm{and}{\mathrm{O}}_2$

• A. Pink
• B. Yellow
• C. Green
• D. White

Answer 1

The correct option is B

Yellow

Explanation for Correct option

Option (B) Yellow

• Lead oxide is a compound which is insoluble in water or dark alcohol. The reaction take place as follows :
• ${\mathrm{PbO}}_2\left(\mathrm{s}\right)\to \mathrm{PbO}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)$
• Here, the oxygen gas is evolved in the reaction.
• The colour of the residue $\mathrm{PbO}$ is yellow.
• Hence option B is the answer.

Explanation for incorrect option :

Option (A) Pink.

• Lead oxide does not absorb pink colour radiation.
• Thus it is incorrect.

Option (C) Green

• .Lead oxide absorb in lower frequency such as yellow.
• Thus this is incorrect.

Option (D) White :

• There is a colour shown by-products Lead oxide.
• Thus this option is incorrect.

Hence The colour of the residue is yellow.