Which would you expect to have a higher melting point: sodium chloride, NaCl, or aluminum oxide, Al₂O₃?

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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. NaCl also has ionic bonds, but the charges on the ions are not as great as those in aluminum oxide. Additionally, the larger size of aluminum oxide molecules does not necessarily result in higher melting points. Covalent bonds, as in the case of the aluminum oxide molecule, can also contribute to higher melting points, but that is not the primary reason in this case.

Which Would You Expect to Have a Higher Melting Point