Intermolecular Forces: Liquids, Slids, and Phase Changes

Question 1

The ________ energy in the form of intermolecular forces tends to draw molecules together.

Answer 1

Potential

Question 2

The _______ energy associated with the random motion of the molecules tends to _____ them.

Answer 2

kinetic; disperse

Question 3

The intermolecular forces, potential energy, and kinetic energy explain the __________.

Answer 3

phase changes

Question 4

In a gas, the potential energy (energy of attraction) is _____ relative to the kinetic energy (energy of motion). Thus, on average, the particles are ____ apart.

Answer 4

small; far

Question 5

In a liquid, attractions are _________ because tha particles are stronger because the articles are touching, but they have enough _____________ to move randomly around each other.

Answer 5

stronger; kinetic energy

Question 6

Table 12.1 A Macroscopic Comparison of Gases, Liquids, and Solids

State Shape & Volume Compress. Flow Ability
Solid ______ its own
shape & volume

Gas _____ to shape of
container

Liquid _____ to shape of
container; _____ limited
by suface

Answer 6

Table 12.1 A Macroscopic Comparison of Gases, Liquids, and Solids

State Shape & Volume Compress. Flow Ability
Solid MAINTAINS its own Almost none Almost none
shape & volume

Gas CONFORMS to shape of High High
conainer

Liquid CONFORMS to shape of Very low Moderate
container; VOLUME limited by surface

Question 7

As temperature increases, KE _______, so the faster moving particles overcome attractions more _____.

Answer 7

increases; rapidly

Question 8

As temperature decreases, particles _____, so ______ can pull them together.

Answer 8

slow; attractions

Question 9

Gas to liquid =

Answer 9

Condensation

Question 10

Liquid to gas =

Answer 10

Vaporization

Question 11

Liquid to solid =

Answer 11

Freezing

Question 12

Solid to Liquid =

Answer 12

Melting or Fusion

Question 13

Gas to solid =

Answer 13

Deposition

Question 14

Solid to gas =

Answer 14

Sublimation

Question 15

Condensing, Freezing, Depositing are ______ changes

Answer 15

Exothermic

Question 16

Melting, Vaporzing, Subliming are ______ changes

Answer 16

Endothermic

Question 17

Within a phase, heat flow is accompanied by a _______________, which is associated with a change iin average _____ are the most probable speed of the molecules changes.

Answer 17

Change in temperature; KE

Question 18

The heat released or absorbed depends on the ____ of substance, the molar ___________ for that phase, and the change in _______.

Answer 18

amount; heat capacity; temperature

Question 19

During a phase change, heat flow occurs at a ______ temperature, which is associated with a change in average ______ as the average distance between molecules __________.

Answer 19

constant; PE; changes

Question 20

Phase changes in open containers are _____.

Answer 20

irreversible

Question 21

Phase changes in a closed container are _____.

Answer 21

reversible

Question 22

In a closed container, phase changes are _______ and reach __________.

Answer 22

reversible; equilibrium