Question

determining the number of valence electrons
chlorine, which is used to clean swimming pools,
exists as two chlorine atoms covalently bonded to each
other.
how many valence electrons does one chlorine (cl)
atom have?

Explanation:

Step1: Count valence electrons

Valence electrons are the electrons in the outermost shell. Chlorine's electron configuration ends with \(3s^{2}3p^{5}\). The sum of electrons in \(3s\) and \(3p\) is \(2 + 5=7\). Also, looking at the Lewis dot structure (dots represent valence electrons), we can count 7 dots around each \(Cl\) atom.

Answer:

7