Question

What is the outermost electronic configuration of the halogens?

• A. $n{s}^{2}n{p}^4$
• B. $n{s}^{2}n{p}^5$
• C. $n{s}^{2}n{p}^3$
• D. $n{s}^{2}n{p}^2$

Answer 1

The correct option is B $n{s}^{2}n{p}^5$

The elements of group 17 have seven electrons in the valence shell and hence their general electronic configuration is $n{s}^{2}n{p}^5.$
Thus, they contain one electron less than the nearest inert gas configuration.
For example Fluorine has electronic configuration $1s^{2}2s^{2}2p^5.$ Hence option (a) is correct.