Which would you expect to have a higher melting point: sodium chloride, NaCl, or aluminum oxide, ?

Question

Which would you expect to have a higher melting point: sodium chloride, NaCl, or aluminum oxide,  ?

Quizplus · Accepted Answer

The aluminum oxide has a higher melting point because of the greater charges of the ions, and hence the greater force of attractions between them. The greater the charges on the ions, the stronger the electrostatic forces of attraction holding the ions in the solid lattice, which results in a higher melting point. NaCl is also composed of ions, but they have lower charges than the ions in aluminum oxide, resulting in a lower melting point compared to aluminum oxide. The size of the molecule or covalent bonds within the molecule does not contribute to the melting point in ionic compounds like NaCl or aluminum oxide.

Which Would You Expect to Have a Higher Melting Point