AP Chemistry: Intermolecular Forces & Properties 2

Question 1

Which intermolecular force is responsible for the unusually high boiling point of water compared to H2S?

Accepted Answer

Hydrogen bonding

Answer

Water's O-H bonds enable strong hydrogen bonding, which H2S lacks because sulfur is less electronegative.

Question 2

Which molecule exhibits ONLY London dispersion forces?

Accepted Answer

CH4

Answer

CH4 is nonpolar, so only temporary dipole London dispersion forces operate.

Question 3

As molar mass increases among nonpolar molecules, London dispersion forces generally:

Accepted Answer

Increase

Answer

Larger molecules have more electrons and greater polarizability, strengthening dispersion forces.

Question 4

Which pair of molecules can form hydrogen bonds with each other?

Accepted Answer

NH3 and H2O

Answer

Both NH3 and H2O have H bonded to N or O, allowing hydrogen bonding between them.

Question 5

Dipole-dipole forces occur between molecules that are:

Accepted Answer

Polar

Answer

Permanent dipoles in polar molecules attract one another via dipole-dipole forces.

AP Practice Test