Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : In TlI3, isomorphous to CsI3, the metal is present in +1 oxidation state.
Reason R : Tl metal has fourteen f electrons in its electronic configuration.
In the light of the above statements, choose the most appropriate answer from the options given below :
Solution
A : Due to inert pair effect, Tl is more stable in
+1 oxidation state<br>
Hence TlI<sub>3</sub> and CSI<sub>3</sub> are isomorphous<br><br>
R : Electronic configuration of Tl (81) =
[Xe] 4f<sup>14</sup> 5d<sup>10</sup> 6s<sup>2</sup> 6p<sup>1</sup><br><br>
Both A and R are correct but R is not the
correct explanation of A.
About this question
Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family
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