Explanation:
Chlorine is an element in group 7 on the periodic table.
It is the second element in this group of halogens
The element has a total of 17 electrons:
Ground state configuration = 1s² 2s² 2p⁶ 3s² 3p⁵
Valence electrons are the outermost shell electrons;
From the configuration: 3s² 3p⁵ is the valence shell
Number of electrons = 2 + 5 = 7
