Unit 8: Phase Changes and Thermodynamics

Question 1

Solid

Answer 1

Definite Shape 
Definite Volume 
CANNOT Flow 
Expands Slightly with heat 
Not Compressible

Question 2

Liquid

Answer 2

Definite Volume
No Definite Shape
Expansions
Not Compressible

Question 3

Gas

Answer 3

No Definite Shape
No Definite Volume
Expansion
Compressible

Question 4

Plasma

Answer 4

Composed of electrons and positive ions at temperatures greater than 5000 Celsius

Question 5

Vapor

Answer 5

The gaseous state of a substance that is a solid or liquid at room temperature

Question 6

Volatile

Answer 6

substances that change to a gas easily at room temperature

Question 7

Viscosity

Answer 7

A measure of the resistance of a liquid to flow. Decreases with rising temperature

Question 8

Surface Tension

Answer 8

Measure of the inward pull by particles at the surface

Question 9

For a substance to be solid…..

Answer 9

Strong attractive forces acting between particles in the solid

Question 10

Crystalline Solid

Answer 10

A solid whose atoms, ions, or molecules are arranged in an orderly, geometric, 3-d structure.

Question 11

Vaporization (Endothermic)

Answer 11

Process of which a liquid changes into a gas or vapor

Question 12

Evaporation (Endothermic)

Answer 12

A Cooling process, that requires heat

Question 13

Boiling Point (Endothermic)

Answer 13

Process when the vapor pressure equals the atmospheric pressure and the molecules throughout the liquid have the energy to enter the gas/vapor phase

Question 14

Condensation

Answer 14

Process when gas/vapor turned into liquid. Reverse of vaporization

Question 15

Melting Point

Answer 15

temperature at which the forces holding the particles together are broken and become liquid.

Question 16

Freezing Point

Answer 16

The temperature at which a liquid becomes a crystalline solid. Same as melting point

Question 17

Sublimation

Answer 17

Solid changes directly into a gas

Question 18

Deposition

Answer 18

Gas changes directly into a solid

Question 19

What controls the phase of a substance

Answer 19

Temperature and Pressure

Question 20

Phase Diagram

Answer 20

Graph of pressure vs temperature that shows in which phase a substance exists under different conditions of temperature and pressure.

Question 21

Critical Point

Answer 21

Indicates the critical pressure and temperature above which a substance cannot exist as a liquid. Only can be a gas

Question 22

Triple Point

Answer 22

The point on a phase that represents the temp and pressure at which 3 phases can coexist

Question 23

Negative Slope

Answer 23

Indicates that the solid floats on its liquid

Question 24

Energy

Answer 24

The ability to do work or produce heat

Question 25

Kinetic Energy

Answer 25

the energy of motion

Question 26

Potential Energy

Answer 26

energy due to the composition or position of an object