The diagram shows the electron configuration around the chlorine nucleus. Chlorine has 17 protons. CI
Which of the following correctly completes the statement?
Chlorine has valence electrons, and the effective nuclear charge, Zett, for the chlorine atom shown is
O A. 7,7+
OB. 7,7-
O C. 10,7-
D. 17, 7+

A.

Explanation:

Valence electrons are the number of electrons constituting the outermost shell of an atom. It is also defined as the electrons that take part in the formation of a chemical bond.

The atomic number of chlorine is 17 as it has 17 protons and the electronic configuration will be 2,8,7. Thus the electrons present in the outermost shell are 7 and hence the valence electrons are 7.

Effective nuclear charge is the net positive charge experienced by valence electrons. It is calculated by: Zeff = Z – S

where Z = atomic number , S = number of shielding electrons.

Thus for Chlorine ,