Substances X and Y are both nonpolar. If the volatility of X is higher than that of Y, what is the best explanation? a. X's molecules experience stronger dipole-dipole forces than Y's molecules. b. Y's molecules experience stronger dipole-dipole forces than X's molecules. c. X's molecules experience stronger London dispersion forces than Y's molecules. d. Y's molecules experience stronger London dispersion forces than X's molecules.

Y's molecules experience stronger London dispersion forces than X's molecules.

Explanation:

Volatility of a molecule depends on different intermolecular force such as molecular wight, dipole-dipole attraction force, hydrogen bonding, ionic attraction force.

Non polar molecules are free from dipole-dipole attraction force, hydrogen bonding and ionic interaction forces.

Hence, volatility of non polar molecules depends solely on molecular weight.

We know, higher the molecular weight of a molecule, lower will be its volatility. This phenomenon can be realized in terms of increasing london dispersion force with increase in molecular weight as number of electrons increases (london dispersion force depends primarily on number of electrons).

As volatility of X is higher therefore we can say that london dispersion force is lower in X as compared to Y.

So option d is the best explanation.