For the electrons of oxygen atom, which of the following statemetns correct?

Options

A. `Z_(eff)` for an electron in a 2s orbital is the same as `Z_(eff)` for an electron in a 2p orbital
B. An electron in the 2s orbital has the same energy as an electron in the 2p orbital
C. `Z_(eff)` for an electron in 1s orbital is the same as `Z_(eff)` for an electron in a 2s orbital
D. The two electrons present in the 2s orbital have same spin quantum numbers `m_(s)` but of opposite sign

Answer

D

Explanation

(a) Electrons in 2s and 2p orbitals have different screen effect. Hence, their `Z_(eff)` is different. `Z_(eff)` of 2s orbital `gtZ_(eff)` of 2p orbital.
(b) Energy of 2s orbital `lt` energy of 2p orbital. Hence, it is not correct.
( c) `Z_(eff)` of 1s orbital `neZ_(eff)` of 2s orbital
Hence, it is incorrect.
(d) For the two electrons of 2s orbital, the value of `m_(s)` is `+1/2and-1/2`.
Hence, it is correct.