Question

In multi electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields?

• A. n = 1, l = 0, m = 0 and n = 2, l = 1, m = 1
• B. n = 2, l = 0, m = 0 and n = 1, l = 0, m = 0
• C. n = 2, l = 1, m = 1 and n = 2, l = 0, m = 0
• D. n = 3, l = 2, m = 1/-1

Answer 1

Answer: (D)

n = 3, l = 2, m = 1/-1

The quantum numbers $n=3,l=2,m=1/-1$ refer to 3d orbital. In the absence of electrical and magnetic field, they are degenerate. Thus they will have same energy level.