Question

Assertion :$Pb{I}_4$ doesn't exist and converts into $Pb{I}_2$ and $I_2$ spontaneously at room temperature but $PbC{l}_4$ needs heating to convert into $PbC{l}_2$ and $C{l}_2$. Reason: $P{b}^{2+}$ is more stable than $P{b}^{4+}$ due to inert pair effect.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is correct but Reason is not correct.

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.

Statement-1 : $Pb{l}_4$ doesn't exist and converts into $Pb{l}_2$ and $l_2$ spontaneously at room temperature but $PbC{l}_4$ needs heating to convert into $PbC{l}_2$ and $C{l}_2$
$P{b}^{4+}$ is a strong oxidising agent whereas iodide ion is strong reducing agent. Hence, $P{b}^{4+}$ cannot survive in presence of iodide ion and get reduced to $P{b}^{2+}$
$P{b}^{4+}+2I^{-}\to P{b}^{2+}+I_2$

Statement-2 : $P{b}^{2+}$ is more stable than $P{b}^{4+}$ due to inert pair effect as s electrons do not participate in bonding.
Hence, both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.