Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom? Choose the correct answer from the options given below :
- (A) and (B) only
- (A) and (C) only
- (B) and (D) only
- (C) and (D) only
Answer
(4) (C) and (D) only
Solution
For the hydrogen atom (one electron) the energy of an orbital depends only on the principal quantum number n: En = - 2.18 10-18n2 J.
So 2s = 2p, 3s = 3p = 3d, and energy increases with n.
(A) 1s (n = 1) < 2p (n = 2) < 3d (n = 3) < 4s (n = 4): correct.
(B) 1s < 2s = 2p < 3s = 3p: correct.
(C) shows 2s < 2p and 3s < 3p: not correct for hydrogen.
(D) shows 4s < 3d: not correct for hydrogen (3d, n = 3, is lower than 4s).
Not correct: (C) and (D).
Answer: (4)