Question 1

Which of the following best explains why water forms a nearly perfect sphere in the absence of gravity, such as on the International Space Station?

Accepted Answer

Intermolecular forces cause water molecules to stick together, minimizing surface area.

Question 2

Which property of water is vital for the development of life as we know it, and is unusual compared to most other substances?

Accepted Answer

The density of ice is less than that of liquid water.

Question 3

Which of the following statements about the compressibility of gases and liquids is correct?

Accepted Answer

Gases are compressible because there is a lot of empty space between particles.

Question 4

Which of the following best describes a crystalline solid?

Accepted Answer

A solid with particles arranged in an orderly, geometric pattern.

Question 5

Which of the following phase changes is endothermic and requires energy input to overcome intermolecular attractions?

Accepted Answer

Vaporization

Question 6

Which type of intermolecular force is present in all molecules and atoms, regardless of polarity?

Accepted Answer

Dispersion (London) forces

Question 7

Why do straight-chain alkanes have higher boiling points than their branched-chain isomers with the same molar mass?

Accepted Answer

Straight chains have more surface-to-surface contact, leading to stronger dispersion forces.

Question 8

Which of the following molecules can form hydrogen bonds with itself?

Accepted Answer

NH\_3

Question 9

A student observes that acetone evaporates much faster than water at room temperature. Which statement best explains this observation?

Accepted Answer

Acetone has weaker intermolecular forces than water.

Question 10

Which of the following best describes the relationship between vapor pressure and intermolecular forces?

Accepted Answer

Weaker intermolecular forces result in higher vapor pressure.

Question 11

Which equation would you use to calculate the heat required to raise the temperature of 1.00 mole of ice from -25.0°C to 0.0°C?

Accepted Answer

$q = m C_s \Delta T$

Question 12

Which of the following statements about the heating curve of water is correct?

Accepted Answer

During boiling, the temperature remains constant until all the liquid has vaporized.

Question 13

Which of the following best explains why water is an excellent solvent for ionic compounds?

Accepted Answer

Water forms ion-dipole attractions with ions, stabilizing them in solution.

Question 14

A liquid rises in a thin glass tube due to capillary action. Which combination of forces is responsible for this phenomenon?

Accepted Answer

Both adhesive forces (liquid-glass) and cohesive forces (liquid-liquid).

Question 15

Which of the following statements about surface tension is correct?

Accepted Answer

Surface tension is higher for liquids with stronger intermolecular forces.

Question 16

Which of the following best describes the process of sublimation?

Accepted Answer

A solid changes directly to a gas.

Question 17

Which of the following is the strongest type of intermolecular force present in a mixture of NaCl (sodium chloride) dissolved in water?

Accepted Answer

Ion-dipole forces

Question 18

Which of the following statements about the boiling point of a liquid is correct?

Accepted Answer

The boiling point is the temperature at which the vapor pressure equals the external pressure.

Question 19

Which of the following factors will increase the rate of evaporation of a liquid?

Accepted Answer

Increasing the temperature of the liquid.

Question 20

Which of the following best describes what happens at the critical point of a substance?

Accepted Answer

The distinction between liquid and gas disappears, forming a supercritical fluid.

Liquids, Solids, and Intermolecular Forces: Structure, Properties, and Phase Changes

Study Guide - Practice Questions