Which of the following sets of quantum numbers is correct for an electron in 3d orbital.

Options

A. n=3, l=2, m= -3, s= +`(1)/(2)`
B. n=3, l=3, m= +3, s= -`(1)/(2)`
C. n=3, l=2, m= -2, s= +`(1)/(2)`
D. n=3, l=2, m= -3, s= -`(1)/(2)`

Answer

C

Explanation

In order to find all the four quantum numbers for an electron in 3 d-orbital, follow the following steps:
Step I
First find the value of n (principal quantum numbers) for the given electron. In this case, it is 3 or n=3
Step II
Values of l never be greater than n and possible values of l for a given value of n is 0 to n-1. Therefore, l=(n-1)=(3-1)=2.
Step III
Values of m varies from -1 to +1 including 0. Hence, the values of m are -2,-1,0,+1,+2.
Step IV
Value of s may be `+(1)/(2)` (clockwise) or `-(1)/(2)` (anticlockwise).
For 3d electron, s=`+(1)/(2)`
Thus, the correct set of quantum numbers for an electron in 3d-orbital is n=3, l=2, m=-2, s=`+(1)/(2)`