Answer:
The weaker interaction in between acetone and chloroform.
Explanation:
The interactions among acetone and acetone or chloroform with chloroform are stronger because both substances are non polar, they are attracted by the interactions called dipole - dipole. This kind of joints use some hydrogen bridge to join the two compounds.
In the case of the interaction acetone chloroform, they are similar but not the same substance, the acetone is less polar than the chloroform, so is necessary to induce a dipole, and this joint is less strong than the normal dipole - dipole.
