Assertion: Magnetic moment values of actinides are lesser than the theoretically predicted values.

Question

Given below are two statements labelled as Assertion (A) and Reason (R)

Assertion: Magnetic moment values of actinides are lesser than the theoretically predicted values.

Reason: Actinide elements are strongly paramagnetic.

Select the most appropriate 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

b. Both A and R are true but R is not the correct explanation of A.

The magnetic moment is less as the 5f electrons of actinides are less effectively shielded which results in quenching of orbital contributions, they are strongly paramagnetic due to presence of unpaired electrons