Physics Test #2

Question 1

Gas

Answer 1

Non-interacting atoms that fill a volume and exert pressure

Question 2

Avogadro’s Number

Answer 2

size of gas samples by measuring in moles

Question 3

Macroscopic Qualities

Answer 3

collection of molecules

Question 4

Microscopic Qualities

Answer 4

individual molecules within collection

Question 5

Kinetic Theory

Answer 5

The macroscopic qualities of a gas are a result of the average microscopic qualities of a very large number of molecules

Question 6

Heat of Transformation

Answer 6

when a sample undergoes a phase change

Question 7

Heat of Vaporization

Answer 7

liquid to gas

Question 8

Heat of Fusion

Answer 8

solid to liquid

Question 9

Phase Change

Answer 9

a substance changes from one form to another

Question 10

Solid

Answer 10

molecules tightly pack, strong bonds, sustains a regular shape

Question 11

Liquid

Answer 11

molecules are loosely packed compared to a solid, weak interaction, molecules move faster than a solid, takes the shape of container

Question 12

Gas

Answer 12

molecules are free to move, little to no interaction with each other, moves at higher speeds, volume expands or contracts to fill container

Question 13

Phase Equillibrium

Answer 13

when two or more phases coexist and are stable

Question 14

Phase Diagram

Answer 14

plots the behavior of the material as a function of pressure and temperature

Question 15

Thermodynamics

Answer 15

the relationship between heat flow, energy, and work in a given system

Question 16

1st Law of Thermodynamics

Answer 16

-the total energy of an isolated system is constant
-any change in a system’s internal energy is related to the heat transferred to the system and the work done by the system

Question 17

Compression

Answer 17

heat must leave the system

Question 18

Expansion

Answer 18

heat must be absorbed by system

Question 19

Isothermal

Answer 19

pressure and volume can change; Q flows in/out

Question 20

Adiabatic

Answer 20

fully insulated, no heat flow

Question 21

Specific Heat

Answer 21

measures how temperature changes with heat flow

Question 22

Heat Engine

Answer 22

converts heat into work

Question 23

Spontaneous

Answer 23

hot to cold

Question 24

2nd Law of Thermodynamics

Answer 24

when two objects are brought into thermal
contact, the spontaneous heat flow is always
from hot to cold

Question 25

Entropy

Answer 25

measure of the amount of disorder in a given system (increases when heat is added)

Question 26

3rd Law of Thermodynamics

Answer 26

no temperature can be lower than absolute zero, no object can ever attain a temperature of absolute zero

Question 27

Calorie

Answer 27

amount of heat needed to raise 1g of water 1° C

Question 28

Conduction

Answer 28

transfer of heat through a substance

Question 29

Convection

Answer 29

as a fluid heats, it becomes less dense, it rises, and colder fluid is now heated

Question 30

Radiation

Answer 30

EM waves carry energy as heat (thermal radiation)

Question 31

Ideal Gas

Answer 31

molecules don’t interact with each other

Question 32

Vapor Pressure

Answer 32

pressure that exists above surface of fluid

Question 33

Engine Concept

Answer 33

can’t be 100% efficient because there would be no flow of heat

Question 34

Why does sweating cool you off?

Answer 34

loss of water from your body (via evaporation) decreases body temp.

Question 35

Sublimation

Answer 35

liquid to vapor

Question 36

Mac and Cheese Boiling on Mountain

Answer 36

boiling point decreases as pressure decreases…therefore water boils at lower temperatures in higher elevations…this lower temperature means the food will need to cook for longer

Question 37

Zeroth Law of Thermodynamics

Answer 37

Two bodies are in equilibrium when their temperatures are equal and unchanging

Question 38

“n”

Answer 38

number of moles

Question 39

“N”

Answer 39

number of molecules