Question

you said that london dispersion forces were the most important force for determining the boiling point of the following substances. based on that and the guidelines to the right, which of the following substances below should have the higher boiling point? molar masses are given in parentheses. which substance has the stronger total intermolecular forces/the higher boiling point? 1. first, look to see if the substance can hydrogen bond. if so, it likely has the strongest intermolecular forces (e.g., hf > hcl). 2. if you are comparing two molecules of very different molar masses, london dispersion forces are more important (e.g., hbr > hcl). 3. if you are comparing two molecules of very similar molar mass, dipole - dipole forces are more important. the molecule with the greater dipole - dipole forces (the greatest electronegativity difference between the atoms within the molecule) will have the greatest boiling point.

Explanation:

Step1: Check hydrogen bonding

Neither \(I_2\) nor \(SO_2\) can hydrogen - bond.

Step2: Compare molar masses

The molar mass of \(I_2\) is \(253.8\ g/mol\) and that of \(SO_2\) is \(64.1\ g/mol\). Since \(I_2\) has a much larger molar mass.

Step3: Determine intermolecular forces

According to the rule (when comparing two molecules of very different molar masses, London dispersion forces are more important), \(I_2\) has stronger London dispersion forces.

Answer:

\(I_2\) has the higher boiling point.