D And F Block Elements Question 2
Question 2 - 2024 (01 Feb Shift 2)
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : In aqueous solutions $Cr^{2+}$ is reducing while $Mn^{3+}$ is oxidising in nature.
Reason (R) : Extra stability to half filled electronic configuration is observed than incompletely filled electronic configuration.
In the light of the above statement, choose the most appropriate answer from the options given below:
(1) Both (A) and (R) are true and (R) is the correct explanation of (A)
(2) Both (A) and (R) are true but (R) is not the correct explanation of (A)
(3) (A) is false but (R) is true
(4) (A) is true but (R) is false
Show Answer
Answer (1)
Solution
$Cr^{2+}$ is reducing as it configuration changes from $d^{4}$ to $d^{3}$ due to formation of $Cr^{3+}$, which has half filled $t _2 g$ level, on other hand, the change $Mn^{3+}$ to $Mn^{2+}$ result half filled $d^{5}$ configuration which has extra stability.
