Chemistry - Trimester 3 Final Flashcards Preview

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Flashcards in Chemistry - Trimester 3 Final Deck (120):
1

compressibility

a measure of how much the volume of matter decreases under pressure

2

Boyle's Law

P1V1 = P2V2

3

Charle's Law

V1/T1 = V2/T2

4

Gay-Lussac's Law

P1/T1 = P2/V2

5

combined gas law

P1V1/T1 = P2V2/T2

6

ideal gas constant

R = 8.31 ( L x kPa)/(K x mol)

7

ideal gas law

PV = nRT

it describes the behavior of the gas

8

partial pressure

the contribution each gas in a mixture of gases makes to the total pressure

9

Dalton's Law of partial pressure

at constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the component gases

Ptotal = P1 + P2 + P3 + ... etc...

10

diffusion

the tendency of molecules to move toward areas of lower concentration until the concentration is uniform throughout

11

effusion

process that occurs when a gas escapes through a tiny hole in its container

12

Graham's Law of effusion

square root of... molar mass of B / molar mass of A

13

aqueous solution

water that contains dissolved substances

14

solvent

dissolving medium in a solution

15

solute

dissolved particles in a solution

16

solvation

a process that occurs when an ionic solute dissolves

17

electrolyte

what are electrolytes?

a compound that conducts an electric current when it is in an aqueous solution or in the molten state

ionic compounds

18

nonelectrolyte

a compound that does not conduct an electric current in aqueous solution or in the molten state

19

strong electrolyte

a solution in which a large portion of the solute exists as ions

20

weak electrolyte

a solution that conducts electricity poorly because only a fraction of the solute exists as ions

21

water of hydration

water molecules that are an integral part of a crystal structure

22

hydrate

a compound that has a specific number of water molecules bound to each formula unit

23

anhydrous

describes a substance that does not contain water

24

effloresce

to lose water of hydration; the process occurs when the hydrate has a vapor pressure higher than that of water vapor in the air

25

hygroscopic

a term describing salts and other compounds that remove moisture from the air

26

desiccant

a hygroscopic used as a drying agent

27

deliquescent

describes a substance that removes sufficient water from the air to form a solution; the solution

28

saturated solution

a solution containing the maximum amount of solute for a given amount of solvent at a constant temperature and pressure

29

solubility

the amount of a substance that dissolves in a given quantity of solvent at specified conditions of temperature and pressure to produce a saturated solution

30

unsaturated solution

a solution that contains less solute than a saturated solution at a given temperature and pressure

31

miscible

describes liquids dissolve in one another in all proportions

32

immiscible

describes liquids that are insoluble in one another

ex. oil and water

33

supersaturated solution

a solution that contains more solute than it can theoretically hold at a given temperature

34

Henry's Law

states that at a given temp., the solubility (S) of a gas in a liquid is directly proportional to the pressure (P) of the gas above the liquid

S1/P1 = S2/P2

35

concentration

a measurement of the amount of solute that is dissolved in a given quantity of solvent, usually expressed as mol/L

36

dilute solution

a solution that contains a small amount of solute

37

concentrated solution

a solution containing a large amount of solute

38

molarity (M)

moles of solute / 1 liter of solution

39

thermochemistry

the study of energy changes that occur during chemical reactions and changes in state

40

chemical potential energy

energy stored in chemical bonds

41

heat

(q) energy that transfers from one object to another because of a temperature difference between the objects

42

system

a part of the universe on which you focus your attention

43

surroundings

everything in the universe outside of the system

44

law of conservation of energy

no energy created nor destroyed

45

endothermic process

process that absorbs heat from the surroundings

46

exothermic process

process that releases heat to its surroundings

47

heat capacity

amount of heat needed to increase the temperature of an object exactly 1°C

48

specific heat

the amount of heat needed to increase the temperature of 1g of a substance 1°C

also called specific heat capacity

49

calorimetry

the precise measurement of heat flow out of a system for chemical and physical processes

50

calorimeter

an insulated device used to measure the absorption or release of heat in chemical or physical processes

51

enthalpy

(H) the heat content of a system at constant pressure

52

thermochemical equation

a chemical equation that includes the enthalpy change

53

heat of reaction

the enthalpy change for a chemical exchange exactly as it is written

54

heat of combustion

the heat of reaction for the complete burning of one mole of a substance

55

molar heat of fusion

S --> L

56

molar heat of solidification

L --> S

57

molar heat of vaporization

L --> G

58

molar heat of condensation

G --> L

59

molar heat of solution

the enthalpy change caused by the dissociation of one mole of a substance

60

rate

describes the speed of change over an interval of time

61

collision theory

atoms, ions, and molecules can react to form products when they collide, provided that the particles have enough kinetic energy

62

activation energy

the minimum energy colliding particles must have in order to react

63

activated complex

an unstable arrangement of atoms that exists momentarily at the peak of the activation energy barrier

called transition state

64

inhibitor

a substance that interferes with the action of a catalyst

65

reversible reaction

a reaction in which the conversion of reactants into products and the conversion of products into reactants occur simultaneously

66

Le Chatelier's Principle

when a stress is applied to a system in dynamic equilibrium, the system changes in a way that relieves the stress

67

chemical equilibrium

a state of balance in which the rates of the forward and reverse reactions are equal

68

equilibrium position

the relative concentrations of reactants and products of a reaction that has reached equilibrium

69

equilibrium constant

(Keq) the ratio of product concentrations to reactant concentrations at equilibrium, with each concentration raised to a power equal to the number of moles of that substance in one balanced chemical equation

70

hydronium ion

(H3O) the positive ion formed when a water molecule gains a hydrogen ion

71

conjugate acid

particle formed when a base gains a hydrogen ion

72

conjugate base

the particle that remains when an acid has donated a hydrogen ion

73

conjugate acid-base pair

two substances that are related by the loss or gain of a single hydrogen ion

74

amphoteric

a substance that can act as both an acid and a base

75

self-ionization

a term describing the reaction in which two water molecules react to produce ions

76

neutral solution

an aqueous solution in which the concentrations of hydrogen and hydroxide ions are equal

has a pH of 7.0

77

ion-product constant for water (Kw)

[H+][OH-] = 1 x 10^-14

78

acidic solution

any solution in which the hydrogen-ion concentration is greater than the hydroxide-ion concentration

79

basic solution

any solution in which the hydroxide-ion concentration is greater than the hydrogen-ion concentration

80

pH (3)

number used to denote the acidity of a substance

- 6 and under = acid
- 8 and higher = base

81

strong acid

an acid that is completely (or almost completely) ionized in aqueous solution

82

weak acid

an acid that is only slightly ionized in aqueous solution

83

acid dissociation constant (Ka)

the ratio of the concentration of the dissociated form of an acid to the undissociated form

84

strong base

a base that completely dissociates into metal ions and hydroxide ions in aqueous solution

85

weak base

a base that reacts with water to form the hydroxide ion and the conjugate acid of the base

86

base dissociation constant (Kb)

(Kb) the ratio of the concentrations of the conjugate acid times the concentration of the hydroxide ions to the concentration of the base

87

neutralization reaction

a reaction in which an acid and a base react in an aqueous solution to produce a salt and water

88

titration

process used to determine the concentration of a solution in which a solution of known concentration is added to a measured amount of the solution of unknown concentration until an indicator signals the end point

89

standard solution

a solution of known concentration used in carrying out titration

90

equivalence point

the point in a titration where the number of moles of hydrogen ions equals the number of moles of hydroxide ions

91

end point

the point in a titration at which the indicator changes color

92

How to find [H+]

[H+] = 10^-pH

93

How to find [OH-]

10^-pOH

94

How to find pH

pH = -log [H+]

95

How to find pOH

pOH = -log [OH-]

96

__ + __ = 14

pH + pOH = 14

97

3 factors that affect gas pressure?

amount of gas (concentration)

volume (in liters)

temperature (T in kelvins)

98

Real Gas vs Ideal Gas

Real - actual gas, high pressures, low temps

99

how to find the number of moles of the gas?

use the ideal gas law -- PV = nRT

100

What does STP stand for?

what are STP conditions

Standard Temperature and Pressure

Standard Temp = 0°C (273K)
Standard Pressure = 1atm (760mmHg or 760 torr)

101

what substances dissolve most readily in water

ionic compounds and polar covalent bonds

102

why are all ionic compounds electrolytes?

because they dissociate into ions

103

% by mass H2O =

mass of water / mass of hydrate (ex. 5H20, 5 x mass of H2O) x 100%

104

what factors affect how fast a substance dissolves? (3)

agitation (rate of stirring/shaking)
temperature
particle size of solute (surface area)

105

What factors affect the solubility of a substance?

temperature affects solubility of solid, liquid, and gases

temp and pressure affects the solubility of gaseous solutes

106

Percent by volume formula

volume of solute / volume of solution x 100%

107

Percent by mass formulas

mass of solute / mass of solution x 100%

108

how to find the specific heat of a substance

q / m x △T

units = J/(g°C)

109

Energy

heat transfer or work

110

what two factors does the heat capacity of an object depend on? (2)

its mass and chemical composition

111

factors that affect the rate of a chemical reaction (4)

temperature

concentration

particle size

use of a catalyst

112

stressors that upset the equilibrium of a chemical system (3)

changes in concentration

changes in temp

changes in pressure

113

what is used to measure pH (2)

pH meters

acid-base indicators

114

kinetic molecular theory (3)

1. particles in a gas are considered to be small, hard spheres with an insignificant volume
2. the motion of the particles in a gas is rapid, constant, and random
3. all collisions b/t particles in a gas are perfectly elastic

115

solutions are...

homogeneous mixtures

stable

116

When Keq has a large value such as ...?

3.1 x 10^11, the reaction mixture at equilibrium will consist mainly of product

117

When Keq has a small value such as...?

3.1 x 10^-11, the mixture at equilibrium will consist mainly of reactant

118

What value would Keq be at an intermediate value? (2)

what does it mean?

0.15 or 50

there is a significant amount of both reactant and product

119

Arrhenius definition of an acid and a base? (2)

acids = hydrogen-containing compounds that ionize to yield hydrogen ions (H+)

base = compounds that ionize to yield hydroxide ions (OH-)

120

Bronsted Lowry definition of an acid and a base

acid = hydrogen-ion donor

base = hydrogen-ion acceptor