Question

Given below are two statements :one is labelled as Assertion $A$ and the other is labelled as Reason $R$
Assertion A : In $T\ell I_3,$ isomorphous to $Cs{I}_3,$ the metal is present in $+1$ oxidation state.
Reason R : $T\ell$ metal has fourteen $f$ electrons in the electronic configuration.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. $A$ is correct but $R$ is not correct
• B. Both $A$ and $R$ are correct and $R$ is the correct explanation of $A$.
• C. $A$ is not correct but $R$ is correct
• D. Both $A$ and $R$ are correct but $R$ is $NOT$ the correct explanation of $A$.

Answer 1

Answer: (D)

$T\ell I_3\Rightarrow \left(T{\ell }^{\oplus }\&I_3^{\ominus }\right)$
$Cs{I}_3\Rightarrow \left(C{s}^{\oplus };\&I_3^{\ominus }\right)$
[Both have same crystalline structure is called isomorphous]
$T{\ell }_{(81)}^{\oplus }=\left[X{e}_{54}\right]4f^{14},5d^{10},6s^2$
(It is correct due to present $14f$ electrons in $T{\ell }^{\oplus }$ ion)