Final answer:
In CH₃CH(OH)CH₃, the substance with the weakest intermolecular forces will be the least soluble.
Step-by-step explanation:
The intermolecular forces that determine solubility in CH₃CH(OH)CH₃ are hydrogen bonding and dipole-dipole interactions. In general, substances with stronger intermolecular forces are more soluble in CH₃CH(OH)CH₃.
Among the given options, the substance with the weakest intermolecular forces will be the least soluble in CH₃CH(OH)CH₃.
a) CH₃Cl experiences dispersion forces and dipole-dipole interactions, but it does not have hydrogen bonding. Therefore, it will have weaker intermolecular forces compared to the other options. Thus, CH₃Cl is the least soluble in CH₃CH(OH)CH₃.