Question

Which of the following ions does not have the same electronic configuration as the others in the list?

a)as
b)ga⁻
c)se²
d)br²⁻

Answer 1

The ion that does not have the same electronic configuration as the others in the list is Ga⁻.

Step-by-step explanation:

The electronic configurations of the ions are as follows:

a) As³-: 1s² 2s² 2p⁶ 3s² 3p⁶

b) Ga⁻: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶

c) Se²-: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶

d) Br²⁻: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶

Comparing the electronic configurations, we can see that Ga⁻ does not have the same electronic configuration as the other ions in the list.