Lesson 3: Phase Change

Question 1

Phase changes occur with change in _________

Answer 1

temperature

Question 2

solid to liquid

Answer 2

melting

Question 3

liquid to gas

Answer 3

vaporization

Question 4

gas to solid

Answer 4

deposition

Question 5

gas to liquid

Answer 5

condensation

Question 6

liquid to solid

Answer 6

freezing

Question 7

a plot of temperature and heat added to the substance

Answer 7

heating curve

Question 8

When a substance is heated, the added energy is used by
the substance in either of two ways:

Answer 8

a.) The added heat increases the kinetic energy of the particles, and the particles move faster.
b.) The added heat is used to break attractive forces between particles. There is no observed increase in temperature when this happens.

Question 9

The removal or release of heat results in two ways:

Answer 9

a.) A decrease in kinetic energy of the particles. The motion of the particles slow down.
b.) Forces of attraction are formed, and a phase change may occur. No change in temperature is observed.

Question 10

summarizes the conditions at which a substance exists as a solid, liquid, or gas

Answer 10

phase diagram

Question 11

The point at which all three curves meet, which is the only condition under which all three phases can be in equilibrium with one another.

Answer 11

Triple point

Question 12

A point on a phase diagram at which both the liquid and gas phases of a substance areindistinguishable.

Answer 12

Critical point