How do ionic and molecular compounds compare in terms of boiling points?
1 Answer
Ionic compounds have higher boiling points.
The attractive forces between ions are much stronger than those between covalent molecules. It takes about 1000 to 17 000 kJ/mol to separate the ions in ionic compounds. It takes only 4 to 50 kJ/mol to separate the molecules in covalent compounds.
The higher attractive forces cause ionic compounds to have higher boiling points. For example, sodium chloride boils at 1413 °C. Acetic acid is a molecular compound with almost the same molecular mass as NaCl. It boils at 118 °C.
