Question

Given below are two statements :

Statement - I : $Ce{O}_2$ can be used for oxidation of aldehyde and ketones.

Statement - II : Aqueous solution of $EuS{O}_4$ is a strong reducing agent.

In the light of the above statements , choose the correct answer from the options given below :

JEE MAINS 2021

• A. Statement I is true but Statement II is false
• B. Both Statement I and Statement II are true
• C. Statement I is false but Statement II is true
• D. Both Statement I and Statement II are false

Answer 1

The correct option is B Both Statement I and Statement II are true

$Ce$ and $Eu$ have stable oxidation state of +3.
The +3 oxidation state of lanthanide is most stable and therefore lanthanide in +4 oxidation state has strong tendence to gain electron and converted into +3 and therefore act as strong oxidizing agent. $Ce{O}_2$ is used to oxidized alcohol aldehyde and ketones. Lanthanide in $+2$ oxidation state has strong tendency to loss electron and convert into $+3$ oxidation state therefore act as strong reducing agent.
So $C{e}^{+4}{O}_2$ acts as oxidizing agent to get reduced to +3 and $E{u}^{+2}{O}_4$ acts as reducing agent to get oxidized to +3 .