Question

which of the following lewis structures correctly represent cacl2?

Explanation:

Step1: Analyze calcium and chlorine

Calcium (Ca) is a metal in group 2, it loses 2 electrons to form a $Ca^{2 + }$ ion. Chlorine (Cl) is a non - metal in group 17, it gains 1 electron to form a $Cl^{-}$ ion.

Step2: Determine Lewis structure

In $CaCl_{2}$, there is one $Ca^{2+}$ ion and two $Cl^{-}$ ions. The Lewis structure should show the $Ca^{2+}$ ion and two $Cl^{-}$ ions with their full valence - shell electrons (8 electrons for $Cl^{-}$ represented by dots around the Cl symbol). The correct Lewis structure has brackets around the $Cl^{-}$ ions to indicate the negative charge.

Answer:

The second option (the one with $Ca^{2+}$ in the middle and two $[:Cl:]^{-}$ ions on either side) is correct as it properly represents the ionic nature of $CaCl_{2}$ with the correct charges and electron - dot representation for the chloride ions.