Question

Complete the sentences to best explain the ranking.

Answer 1

Answer:

dipole-dipole forces, ion-dipole forces, higher molar mass, hydrogen bonding, stronger intermolecular forces

Explanation:

1. H₂S and H₂Se exhibit the following intermolecular forces: dipole-dipole forces and ion-dipole forces.  These molecules have a bent geometry, thus, a dipolar moment which makes them dipoles. When they are in the aqueous form they are weak electrolytes whose ions interact with the water dipoles

2. Therefore, when comparing H₂S and H₂Se the one with a higher molar mass has a higher boiling point.  In this case, H₂Se has a higher boiling point than H₂S due to its higher molar mass.

3. The strongest intermolecular force exhibited by H₂O is hydrogen bonding.  This is a specially strong dipole-dipole interaction in which the positive density charge on the hydrogens is attracted to the negative density charge on the oxygen.

4. Therefore, when comparing H₂Se and H₂O the one with stronger intermolecular forces has a higher boiling point. That's why the boiling point of H₂O is much higher than the boiling point of H₂Se.