Question

Write electron configuration for H+ , Na+, O2-

Answer 1

(a) H- ion
The electronic configuration of H atom is 1s1.
A negative charge on the species indicates the gain of an electron by it.
∴ Electronic configuration of H- = 1s2
(b) Na+ ion

The electronic configuration of Na atom is 1s2 2s2 2p6 3s1.
A positive charge on the species indicates the loss of an electron by it.
∴ Electronic configuration of Na+ = 1s2 2s2 2p 6 3s0 or 1s2 2s2 2p6
(c) O2- ion
The electronic configuration of 0 atom is 1s2 2s2 2p4.
A dinegative charge on the species indicates that two electrons are gained by it.

Answer 2

(i) (a) H– ion

The electronic configuration of H atom is 1s1.(atomic number = 1)

∴ Electronic configuration of H– = 1s2

 

(b) Na+ ion

The electronic configuration of Na atom is 1s2 2s2 2p6 3s1.(atomic number = 11)

∴ Electronic configuration of Na+ = 1s2 2s2 2p6 3s0  Or  1s2 2s22p6

 

(c) O2– ion

The electronic configuration of 0 atom is 1s2 2s2 2p4.(atomic number = 8)

∴ Electronic configuration of O2– ion = 1s2 2s2 p6