Question

What does the magnitude of the dispersion force depend on? How can you predict the magnitude of the dispersion force for closely related elements or compounds? Match the items in the left column to the appropriate blanks in the sentences on the right.

The magnitude of the dispersion force depends on how easily the electrons in the atom or molecule can move or polarize in response to______dipole (a temporary change in charge distribution), which in turn depends on the size (or volume) of the electron cloud. A larger electron cloud results in a more______ dispersion force because the electrons are held ____tightly by the nucleus and can an induced therefore polarize_____If all other variables are constant, the dispersion force ______less with increasing molar mass because molecules or atoms of higher molar mass generally have______lower electrons dispersed over a _______volume. The shape of the molecules can also affect the greater magnitude of the dispersion forces. The _____the area of interaction between two molecules, the larger the dispersion forces.
a. with difficulties
b. an instantaneous
c. more
d. an induced
e. less
f. lower
g. greater
h. a permanent
i. decreases
j.more easily
k.increases

Answer 1

The strength of dispersion forces depends on the polarizability of an atom or molecule, which is affected by the size of the electron cloud and molar mass; larger clouds and masses lead to stronger forces. The shape of the molecule, influencing the area of interaction, also plays a role.

Step-by-step explanation:

The magnitude of the dispersion force depends on how easily the electrons in the atom or molecule can move or polarize in response to an instantaneous dipole (a temporary change in charge distribution), which in turn depends on the size (or volume) of the electron cloud. A larger electron cloud results in a more powerful dispersion force because the electrons are held less tightly by the nucleus and can polarize more easily. If all other variables are constant, the dispersion force increases with increasing molar mass because molecules or atoms of higher molar mass generally have more electrons dispersed over a greater volume. The shape of the molecules can also affect the magnitude of the dispersion forces. The larger the area of interaction between two molecules, the larger the dispersion forces.