Not in the slightest.
First, they are not molecules, they are ionic compounds.
Second, they are two very different substances.
CaO is calcium oxide, consisting of the elements calcium and oxygen. It is commonly called lime or quicklime. It is very alkaline (basic) and is commonly used to neutralize acidic soil.
NaCl is sodium chloride, consisting of the elements sodium and chlorine. It is commonly called salt or table salt. It has no acid/base properties. It is commonly used to flavor food and melt ice
Na2SO4 and NaCl
ionic - Sodium Chloride Covalent - Water ionic - Sodium Chloride Covalent - Water
NaCl is a molecule composed of two atoms Na and Cl.
NaCl
CaO is ionic as the electronegativity difference between the two atoms is above 1.7
One atom of chlorine per molecule of NaCl.
A molecule of NaCl (Sodium chloride) is comprised of Sodium and Chlorine.
NaCl KCl MgF2 CaF2 CaCl2 LiCl MgO CaO Na2O K2O
Today NaCl is considered the formula unit of sodium chloride, not the true chemical formula of the molecule; NaCl form very complex lattices, as other ionic salts.
NaCl
The term molecule is not adequate for sodium chloride because NaCl form large lattices. More exact is formula unit - NaCl.
Cl2 is covalent. NaCl is ionic.