Based on the molecular structures of chloromethane and methane shown, a student makes the claim that a pure sample of chloromethane has stronger intermolecular forces than a pure sample of methane has.

Yes, the claim that a pure sample of chloromethane has stronger intermolecular forces than a pure sample of methane is correct.

Intermolecular forces are weaker forces (Van Deer Waal forces) of attraction that pull molecules together. They are weaker than covalent bonds and they arise as a result of interaction between positively charged and negatively charged species (polarity).

The types of Van Deer Waal forces that exist are in decreasing order are:

If we consider the molecular structures of both chloromethane and methane, we will realize that chloromethane has a higher intermolecular force than methane. This is due to the bond polarizability in chloromethane that does not exist in methane.

Thus, chloromethane exhibit a dipole-dipole force of attraction while methane undergoes a weak induced dipole-induced dipole force due to its lower polarity than chloromethane.

Learn more about bond polarity here:

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Yes, chloromethane has stronger intermolecular forces than a pure sample of methane has.

Explanation:

In both methane and chloromethane, there are weak dispersion forces. However, in methane, the dispersion forces are the only intermolecular forces present. Also, the lower molar mass of methane means that it has a lower degree of dispersion forces.

For chloromethane, there is in addition to dispersion forces, dipole-dipole interaction arising from the polar C-Cl bond in the molecule. Also the molar mass of chloromethane  is greater than that of methane implying a greater magnitude of dispersion forces in operation.

Therefore, chloromethane has stronger intermolecular forces than a pure sample of methane has.