Can someone help me answer this!

Question

Magnesium oxide, MgO, and magnesium chloride, MgCl2, are very similar, white ionic solids with the following properties:

Compound	Melting Point (oC)	Solubility
MgO	2800	Insoluble
MgCl2	1412	Very soluble

a) Give the formula of the ions of each compound

b) Account for the drastic difference in physical properties

Answer 1

a). MgO: Mg²⁺ and O^2-

MgCl₂: Mg²⁺ and Cl^-

b). MgO is a covalent molecular compound whereas MgCl₂ is an ionic compound. MgCl₂ will ionize as an electrolyte but MgO will not since it is a non electrolyte. This also explains the difference in solubility.