Unit 1: Physical and Chemical Equilibrium Flashcards

1
Q

If samples contain the same molecule at the same temperature, the samples will have the same ________________________

A

vapor pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

condensation

A

gas to liquid
∆H < 0, ∆S < 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

deposition

A

gas to solid
∆H < 0, ∆S < 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sublimation

A

solid to gas
∆H > 0, ∆S > 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

vaporization

A

liquid to gas
∆H > 0, ∆S > 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

freezing

A

liquid to solid
∆H < 0, ∆S < 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

fusion

A

solid to liquid (melting)
∆H > 0, ∆S > 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

ice melts at _°C

A

0°C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

enthalpy (change in ∆H)

A

transfer of heat energy at constant pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

organized molecular motion

A

work

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

entropy (∆S)

A

the dispersal of energy at constant temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

free energy (∆G)

A

the energy available to do work

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

∆G is zero at….

A

phase changes at phase change temp. because that’s when its at equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

for samples with the same compound, the sample with the highest VP will have the highest ___________________

A

temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The normal boiling point is the boiling point at _________

A

1 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A gas cannot be liquefied ____________ its critical temperature

A

above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

supercritical fluid

A

particles have so much kinetic energy
no IMFs
in-between liquid and gas
particles are close together like in liquids or very far apart
going from a gas to a SCF or a liquid to a SCF is NOT a phase transition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

solute

A

can be solid, liquid, or gas
dissolved in the solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

solvent

A

the major component in a solution
usually a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

solution

A

solutes are dissolved into solvents to form solutions
they are homogenous mixtures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When you increase the temperature of a solution that has a solid solute, the solubility ____________.

A

increases
(i.e. more solid dissolves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When you increase the temperature of a solution that has a gaseous solute, the solubility ___________

A

decreases
(i.e. the gas bubbles out of the solution)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Henry’s Law

A

the amount of gas dissolved into a solvent is proportional to the pressure of the gas above the solvent
Cgas (molarity) = Kh (Henry law constant) x Pgas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

You can melt ice by applying ___________ pressure because the solid/liquid line has a ___________ slope

A

higher, negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

triple point

A

the temperature and pressure at which three phases are in equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

∆H solvation =

A

energy released when solute interacts and forms IMFs with the solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

∆H lattice energy =

A

energy required to pull apart solute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Most dissolution processes are _______________ when the solute is a solid.
This is because the ∆HLE is _________ and the ∆Hsolvation is ___________

A

endothermic, positive, negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Dissolution of a gaseous solute =

A

exothermic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

strong electrolytes are molecules that __________ break into 2 or more ions when dissolved in a solvent

A

always

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

strong electrolytes =

A

100% dissociation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

weak electrolytes are molecules that ____________ break into 2 or more ions when dissolved in a solvent

A

sometimes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

weak electrolytes =

A

between 0% and 100% dissociation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

nonelectrolytes are molecules that __________ break into 2 or more ions when dissolved in a solvent

A

never

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

nonelectrolytes =

A

0% dissociation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Molarity

A

the number of moles of solute per liter of solution (unit = mol/L = M)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Molality

A

the number of moles of solute per kilogram of solvent (unit = mol/kg = 𝓂)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Boiling Point Elevation

A

The boiling point of a solution will be higher than the pure substance (ex. salt water will have a higher boiling point than pure water)
∆Tb = iKbm(solute)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Freezing Point Depression

A

The freezing point of a solution will be lower than the pure substance (ex. salt water will have a lower freezing point than pure water)
∆Tf = -iKfm(solute)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Vapor Pressure Lowering (Raoult’s Law)

A

The vapor pressure of a solution will be lower than the pure substance (ex. salt water will have a lower vapor pressure than pure water)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Osmosis

A

Explains the movement of solvent between solutions of different concentrations separated by a semi-permeable membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

the only thing that affects the vapor pressure of a substance is the _______________

A

temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Chemical equilibrium is a ____________ process

A

dynamic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

The reaction quotient is represented by the variable __ and it is used at ______________

A

Q, any point in the reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

The activity of a substance tells us…

A

how the free energy changes during the reaction progression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Equilibrium

A

a reversible chemical reaction or physical change where the rates of the forward and backward reactions are equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

The best mass action expression will show the proper ratio of products to reactants in _________

A

pressure

48
Q

At equilibrium, the system is at the __________ free energy and ∆G is now _______

A

lowest, zero

49
Q

Q is only equal to K at __________

A

equilibrium

50
Q

Kc = Kp when…

A

the number of gas molecules are the same on both sides.

51
Q

When the standard change in free energy (ΔGr°) is negative, the reaction favors the ____________. The point of equilibrium will be closer to the ______________

A

products, product-side

52
Q

When the standard change in free energy (ΔGr°) is positive, the reaction favors the ___________. The point of equilibrium will be closer to the __________.

A

reactants, reactant-side

53
Q

K < 1 and ∆G° > 0

A

reaction favors the reactants

54
Q

K > 1 and ∆G° < 0

A

reaction favors the products

55
Q

Q = K and ∆G = 0

A

reaction is at equilibrium

56
Q

K > 1 and ∆G° > 0

A

does not exist

57
Q

K < 1 and ∆G° < 0

A

does not exist

58
Q

Le Chatelier’s Principle states: If a chemical system at equilibrium experiences a(n) _________, then the equilibrium shifts to counteract the imposed change and a new _____________ is established.

A

change, equilibrium

59
Q

For the dissolution to be endothermic, ∆Hsolution must be __________, so two values must add to a ___________ number

A

positive, positive

60
Q

What increases the solubility of a gas in water?

A

decreasing the temp. of the water
increasing the pressure of the gas above the water

61
Q

Very small K =

A

reactant-favored; makes more reactants, thus more products need to be made to reach equilibrium

62
Q

1-ish K =

A

mix of reactants and products (somewhere in middle)

63
Q

Very large K =

A

product-favored; makes more products, thus more reactants need to be made to reach equilibrium

64
Q

always ignore ________________ in the mass action expression

A

solids and liquids

65
Q

inverse of ln

A

e^x

66
Q

When total pressure increases, a reaction at equilibrium will shift to the side with…

A

fewer number of moles of gas

67
Q

Q < K

A

more reactants than products; not enough products
will shift forward to form more products

68
Q

Q > K

A

more products than reactants; not enough reactants
will shift backward to form more reactants

69
Q

K = _________ energy ratio

A

lowest

70
Q

The melting point is the temp. at which…

A

the solid and liquid phases are in equilibrium

71
Q

the vapor pressure at the boiling point is _____

A

1

72
Q

boiling point is the temp. at which…

A

a liquid’s equilibrium vapor pressure is equal to the pressure exerted on the liquid by its gaseous surroundings

73
Q

concentration =

A

molarity

74
Q

For gases to dissolve in a liquid, the sign for ∆Hsolvation must be ____________

A

negative

75
Q

Polar solvents mix well with…

A

other polar solvents

76
Q

Polar solvents do not mix well with…

A

nonpolar solvents

77
Q

What happens to temp. of solution when gas solute is dissolved into a liquid?

A

increases temp.

78
Q

What happens to temp. of solution when solid solute is dissolved into a liquid?

A

decreases temp.

79
Q

all covalent solutes will have i =

A

1

80
Q

all ionic solutes are __________ electrolytes

A

strong

81
Q

Clausius-Clapeyron Equation

A

ln (P2/P1) = ∆Hvap/R (1/T1 - 1/T2)
R = 8.314 J/mol x K

82
Q

if you increase entropy, you _________ free energy

A

lower

83
Q

VPsolution = Xsolvent - VP°solvent

A

Raoult’s Law (Version #1): whenever you have a solute in a liquid solvent. The solute is usually a solid.

84
Q

Raoult’s Law (Version #1): whenever you have a solute in a liquid solvent. The solute is usually a solid.

A

VPsolution = Xsolvent - VP°solvent

85
Q

Raoult’s Law (Version #2): whenever you want to determine the change in vapor pressure

A

∆VP = -Xsolute x VP°solvent

86
Q

Main Raoult’s Law equation:

A

VPsolution = XaVP°a + XbVP°b

87
Q

The mole fraction axes for Xa on Raoult’s Plot reads ______ to ______

A

left to right

88
Q

The mole fraction axes for Xb on Raoult’s Plot reads ______ to ______

A

right to left

89
Q

Colligative properties are properties of a solution that ______ from the pure solvent, and that ___________________

A

differ, do not depend on what the solute is

90
Q

Colligative properties only depend on the _______________________ in the solution

A

particle concentration

91
Q

The Four Colligative Properties

A

Boiling Point Elevation
Freezing Point Depression
Vapor Pressure Lowering
Osmotic Pressure

92
Q

Osmotic Pressure (π) and formula

A

the pressure needed to maintain equal rates of solvent-to-solution and solution-to-solvent.
π = iMRT

93
Q

higher entropy = ______ free energy = ______ stable

A

lower, more

94
Q

Kc vs. Kp formula

A

Kp = Kc(RT)^∆n

95
Q

K is where reaction is most ______

A

stable

96
Q

Kreverse =

A

1/Kforward

97
Q

reactant-favored spontaneity?

A

non-spon
∆G = (+)

98
Q

product-favored spontaneity?

A

spon
∆G = (-)

99
Q

∆G°

A

change of free energy for standard reaction when all reactants have converted to products under standard conditions

100
Q

∆G

A

change of free energy at specific point in reaction

101
Q

∆G° vs. ∆G formula

A

∆G = ∆G° + RTlnQ

102
Q

K < 1, ∆G =

A

(+)

103
Q

K > 1, ∆G =

A

(-)

104
Q

If heat energy is added to an exothermic reaction, the reaction shifts to add some __________

A

reactants

105
Q

If heat energy is added to an endothermic reaction, the reaction shift to add some __________

A

products

106
Q

What is the only factor that affects K?

A

temperature

107
Q

If we decrease the volume of the container of gases, the pressure inside the container will increase. Reaction will move towards the side of the reaction with…

A

fewer gas molecules

108
Q

If we increase the volume of the container of gases, the pressure inside the container will decrease. Reaction will move towards side of the reaction with…

A

the greater number of gas molecules

109
Q

For only water, 1 mL =

A

1 gram

110
Q

combustion equation

A

fuel + O2 –> CO2 + H20

111
Q

heat of sublimation formula

A

∆Hfus + ∆Hvap = ∆Hsub

112
Q

In general, the smaller the metal, the larger the…

A

∆Hvap because atoms can form stronger interactions with neighboring atoms

113
Q

What is Q at t=0?

A

zero

114
Q

Primary difference between ∆G° and ∆G?

A

entropy

115
Q

Kc and Kp are the equilibrium constants of gaseous mixtures. However, the difference between the two constants is that Kc is defined by _____________, whereas Kp is defined by the ___________________ of the gasses inside a closed system.

A

molar concentrations, partial pressures