1. 2) The vapor pressure of liquid A is lower than that of liquid B at room temperature, also lower
at 60 C. Which of the following statements concerning about the liquids A and B is always true?
A) Both liquids A and B much exhibit hydrogen bonding B) Both liquids A and B much have
ion-induced dipole interactions. C) Both liquids A and B much bave ion-dipole forces D) Both
liquids A and B much have London forces E) Both liquids A and B much have dipole-dipole
forces.
Solution
Factors that affect vapor pressure are:-
1) Temperature: At a higher temperature more molecules have enough energy to escape out from
the liquid. At a lower temperature, fewer molecules have sufficient energy to escape from liquid.
2) Types of Molecules:- The types of Molecules that make up a liquid or a solid determine it's
vapor pressure. If the intermolecular forces between molecules are:
* relatively strong, the vapor pressure will be relatively low.
* relatively weak, the vapor pressure will be relatively high.
So the answer will be option (C) as ion-dipole are stronger in the given case.
NOTE: If the question is multiple correct anwer then option may be (A), (B), (C) also.