Lesson 6

Question 1

They are transformations of matter from one physical state to another. They occur when energy (usually in the form of heat) is added to or removed from a substance.

Answer 1

Phase changes

Question 2

The state of matter without a set shape or volume.

Answer 2

Gas

Question 3

The transition of matter from one state to another.

Answer 3

Phase change

Question 4

The change of the physical state of matter from gas to liquid. The opposite of evaporation.

Answer 4

Condensation

Question 5

The state of matter with a set volume but no set shape.

Answer 5

Liquid

Question 6

The amount of force per unit area.

Answer 6

Pressure

Question 7

The change of the physical state of matter from solid directly to gas. The opposite of deposition.

Answer 7

Sublimation

Question 8

The change of the physical state of matter from gas directly to solid. The opposite of sublimation.

Answer 8

Deposition

Question 9

Anything that both occupies space and has mass.

Answer 9

Matter

Question 10

The amount of space an object occupies.

Answer 10

Volume

Question 11

Measure of increasing kinetic energy from solid to liquid to gas.

Answer 11

Temperature

Question 12

The state of matter with a set volume and a set shape.

Answer 12

Solid

Question 13

The change of the physical state of matter from a liquid to a gas. The opposite of condensation.

Answer 13

Evaporation

Question 14

The amount of matter contained in an object.

Answer 14

Mass

Question 15

Highly ionized (charged) gases that exist at high temperatures.

Answer 15

Plasma

Question 16

The change of the physical state of matter from solid to liquid. The opposite of freezing.

Answer 16

Melting

Question 17

The change of the physical state of matter from liquid to solid. The opposite of melting.

Answer 17

Freezing

Question 18

These two scientific concepts are needed to enable these substances to undergo phase changes.

Answer 18

Temperature and pressure

Question 19

Therefore, _______ and _______ are needed to liquefy gases.

Answer 19

High pressure and low temperature

Question 20

It is the combination of pressure and temperature at which all three phases of matter are at equilibrium. It is the point on a phase diagram at which the three states of matter coexist.

Answer 20

Triple point

Question 21

The merged single phase beyond the temperature of the critical point.
The temperature and pressure corresponding to this are known as the critical temperature and critical pressure.

Answer 21

Supercritical fluid