# Sodium reacts with chlorine to form the compound sodium 2Na + Cl_2 -> 2NaCI. How would you describe, in terms of electron arrangement, the type of bonding in a molecule of chlorine?

The chlorine molecule is represented as $C l - C l$, i.e. $C {l}_{2}$. Between the chlorine atoms, 2 electrons overlap to form a region of high electron density to which the positively charged chlorine nuclei are attracted, such that internuclear repulsion is negated and a net attractive force results. Because the bonding electrons are shared between the nuclei, we conceive that each atom has 8 valence electrons.
Of course, on reaction with sodium, the sodium reduces the chlorine molecule to give $2 \times C {l}^{-}$. The resultant bond between $N {a}^{+}$ and $C {l}^{-}$ is ionic and a non-molecular substance results.