Water (H2O) has a boiling point of 100°C, and hydrogen iodide (HI) has a boiling point of -35.2°C. Why is the boiling point of water higher than that of hydrogen iodide?
because the molar mass of hydrogen iodide is higher than the molar mass of water
because the intermolecular forces in water are stronger than in hydrogen iodide
because water is a covalent substance and hydrogen iodide is an ionic compound
because water is a polar substance and hydrogen iodide is a non-polar substance