Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as $\operatorname{Reason}( R )$
Assertion (A) : The ionic radii of $O ^{2-}$ and $Mg ^{2+}$ are same.
Reason (R) : Both $O ^{2-}$ and $Mg ^{2+}$ are isoelectronic species
In the light of the above statements, choose the correct answer from the options given below

• A. Both (A) and (R) are true and (R) is the correct explanation of (A)
• B. Both (A) and (R) are true but (R) is not the correct explanation of (A)
• C. (A) is true but (R) is false
• D. (A) is false but (R) is true

Answer 1

Answer: (D)

Ionic radius of $O ^{2-}$ is more than that of $Mg ^{2+}$ Both $O ^{2-}$ and $Mg ^{2+}$ are isoelectronic with $10$ electrons