UNIT FIVE

Question 1

kinetic-molecular theory of gases

Answer 1

particles of matter are always in motion

Question 2

ideal gas

Answer 2

imaginary gas that perfectly fits all assumptions of kinetic-molecular theory

Question 3

assumptions of kinetic-molecular theory

Answer 3

1) gases consist of many tiny particles that are far apart
2) collisions between gas particles, particles, container walls are elastic (no net loss of kinetic energy)
3) in constant, rapid motion
4) no forces of attraction/repulsion between particles
5) average kinetic energy of gas particles depends on temperature (KE=1/2 mass x speed)

Question 4

expansion

Answer 4

fills container

Question 5

fluidity

Answer 5

gas particles slide easily due to few attractive forces

Question 6

low density

Answer 6

particles very far apart

Question 7

compressibility

Answer 7

initially far apart can be pushed together

Question 8

diffusion

Answer 8

spontaneous mixing of particles of 2 substances caused by random motion and depends on particle speed, diameter, attractive forces

Question 9

effusion

Answer 9

process where gas particles under pressure pass through tiny openings and is directly proportional to particle velocity

Question 10

barometer

Answer 10

measures atmospheric pressure

Question 11

Boyle’s Law

Answer 11

P1V1 = P2V2

Question 12

Charles’ Law

Answer 12

V1/T1 = V2/T2

Question 13

Gay-Lussac’s Law

Answer 13

P1/T1 = P2/T2

Question 14

Combined Law

Answer 14

(P1V1)/T1 = (P2V2)/T2

Question 15

Ideal Gas Law

Answer 15

PV = nRT

Question 16

Avogadro’s Law

Answer 16

equal volume of gases at the same temperature and pressure has the same number of molecules

Question 17

gas standard molar volume

Answer 17

volume occupied by 1 mole of gas at standard temperature and pressure

Question 18

Graham’s Law of Effusion

Answer 18

rate of effusion of gases at same temperature and pressure are inversely proportional to their square root molar masses

Question 19

liquid

Answer 19

form of matter that has definite volume and takes shape of container

Question 20

fluid

Answer 20

substance that can flow and take the shape of its container

Question 21

properties of liquids

Answer 21

• relatively high density
• relative incompressibility
• ability to diffuse
• surface tension
• evaporation
• boiling

Question 22

crystalline solids

Answer 22

consists of many crystal (most solids) and particles are pattered orderly, geometric and repeating

Question 23

amorphous solids

Answer 23

particles arranged randomly such as plastic and gas

Question 24

equilibrium

Answer 24

dynamic condition where two opposite charges occur at closed rates in equal rates

Question 25

Le-Chatelier's Principle

Answer 25

when equilibrium system is disturbed y application of stress, it attains new equilibrium that minimizes stress

Question 26

volatile liquids

Answer 26

liquids that evaporate easily

Question 27

molar heat of vaporaization

Answer 27

energy required to vaporize one mole of liquid at boiling point, high when intermolecular forces are strong

Question 28

molar heat of fusion

Answer 28

energy required to melt one mole of solid at melting point

Question 29

phase diagrams

Answer 29

graph of pressure versus temperature, shows conditions under which phases exist

Question 30

triple point of a substance

Answer 30

indicates temperature and pressure conditions when solid, liquid, and vapour coexist at equilibrium

Question 31

solution

Answer 31

uniform mixture of two or more substances

Question 32

solvent

Answer 32

component of a solution present in largest amount

Question 33

solute

Answer 33

components of solution present in smaller amounts than solvent

Question 34

solute

Answer 34

components of solution present in smaller amounts than solvent

Question 35

electrolyte

Answer 35

substance that dissolves in water and creates conductive solution, includes all soluble ionic compounds and highly polar molecular compounds

Question 36

nonelectrolyte

Answer 36

dissolves but does not create conductivity, eg sugar

Question 37

solution equilibrium

Answer 37

physical state in which opposing process of dissolution and crystallization occur at equal rates

Question 38

saturated solution

Answer 38

contains maximum amount of dissolved solute

Question 39

supersaturated solution

Answer 39

contains more dissolved solute in same conditions

Question 40

Henry's Law

Answer 40

solubility of gas in a liquid is directly proportional to partial pressure of that gas on surface of liquid

Question 41

molality

Answer 41

amount of solute (moles, n) divided by mass (m) of solvent in kg *m*=n/m

Question 42

molarity

Answer 42

amount of solute divided by volume M=n/V