Assertion : Magnetic moment of `Mn^(2+) " is less than that of " Cr^(2+)`.
Reason : Higher the atomic number smaller is the magnetic moment.

Options

A. If both (A) and (R) are correct and (R) is the correct explanation of(A).
B. If both (A) and (R) are correct, but(R) is not the correct explanation of (A).
C. If(A) is correct, but (R) is incorrect.
D. If both (A) and (R) are incorrect.

Answer

D

Explanation

The magnetic moment is determined by number of unpaired electrons and is calculated by using the formula, `mu = sqrt ( n(n+2))` where n is number of unpaired electrons. It incrcases with increase in number of unpaired electrons hence `Mn^(2+) " will have higher magnetic moment than " Cr^(2+)`