Unit 3: Solubility and Kinetics Flashcards

1
Q

Solubility

A

The maximum amount of solute that can be dissolved in a solvent at equilibrium

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

Unsaturated solution

A

When the solute concentration is less than its equilibrium solubility concentration

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

Saturated solution

A

When a solute concentration is equal to its equilibrium solubility concentration
ex. flat coke

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

Supersaturated solution

A

When a solute concentration is greater than its equilibrium solubility concentration

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

Precipitation Reactions general formula

A

AB(aq) + CD (aq) <=> AD(aq) + CB(s)

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

A double-replacement reaction is where ____________ react to form ____________.

A

dissolved substances, one (or more) solid products

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

The solid that is formed in a double-replacement reaction is known as a ___________.

A

precipitate

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

The solution above the precipitate is called the __________.

A

supernatant

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

The equation in which all ionic species (regardless of their physical state) are kept in their formula units, is called a ______________ or __________________.

A

molecular equation, formula unit equation

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

Total ionic equations

A

include all ions and compounds in the reaction in the form they actually exist in the solution

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

Net ionic equations

A

only include the ions forming a precipitate, and neglect to include ions remaining dissolved in solution (spectators)

Ions that are in the same form on both the reactant side and product side of the equation are canceled

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

Always soluble:

A

Li+ Na+ K+ Rb+ Cs+ NH4+ NO3– ClO3– ClO4– CH3COO–

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

Never soluble (except soluble when bonded with Group 1 elements and NH4+):

A

phosphate: PO43–
carbonate: CO32–
sulfite: SO32–

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

Usually insoluble (except soluble when bonded with Group 1 elements and and NH4+ and some Group 2 elements):

A

OH– S2–

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

When in doubt,

__________ compounds are usually insoluble.

A

Ag, Hg, and Pb

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

Before a solution is saturated, a solid will _____________ dissolve. Once saturation is reached, the rate of dissolution of the solid and the rate of reforming the solid from dissolved ions are _____________ and the system is ___________

A

spontaneously, equal, at equilibrium

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

Compounds that we call insoluble are those whose lowest free energy point for the dissolving process lies …

A

very close to 100% solid reactant(s) and nearly 0% ionic products.

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

The ____________ is the equilibrium constant for the equilibrium between a slightly soluble ionic solid and a solution of its ions when the reaction is written as the solid dissolving into ions.

A

solubility product constant (Ksp)

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

Since there is always only one solid reactant in a solubility chemical equation, there is never a __________ in a Ksp expression.

A

denominator

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

When Qsp > Ksp, the reaction shifts to the ___________

A

reactants (to the left).
For solubility reactions, the solid is the reactant on the left. Thus, if Qsp > Ksp, the compound will precipitate.

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

When Qsp < Ksp, the reaction shifts to the ____________

A

products (to the right).
For solubility reactions, the dissolved ions are the products on the right. Thus, if Qsp < Ksp, the ions remain dissolved.

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

When Qsp = Ksp, the reaction is at _____________.

A

equilibrium

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

molar solubility (x)

A

the number of moles per liter of the compound that will dissolve in a saturated solution

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

just AB dissolving in water
Ksp equation?

A

Ksp = x^2

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

just A2B or AB2 dissolving in water
Ksp equation?

A

Ksp = 4x^3

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

just A3B or AB3 dissolving in water
Ksp equation?

A

Ksp = 27x^4

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

just A2B3 or A3B2 dissolving in water
Ksp equation?

A

Ksp = 108x^5

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

[ion] =

A

(x) (subscript)

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

x =

A

[ion] / subscript

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

to get grams per liter…

A

multiply moles/L x molar mass = g/L

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

to get molar solubility from g/L…

A

divide g/L by molar mass = mol/L

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

Ksp values for 3:2 or 2:3 ratios are ________

A

very small

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

the common ion effect occurs in a solution in which…

A

the same ion is provided by two different compounds.

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

will concentration of Mg2+ be greater if MgF2 is dissolved in pure water or in a solution of 0.1M sodium fluoride?

A

pure water

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

what is the molar solubility (x) of MgF2 in water?

A

Ksp = 4x^3
x = (Ksp/4)^1/3

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

what is the molar solubility (x) of MgF2 in 0.10 M NaF?

A

Ksp = [Mg2+] [F-]^2
solve for [Mg2+]

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

what is the molar solubility (x) of MgF2 in 0.10 M MgNO3?

A

Ksp = [Mg2+] [F-]^2
solve for [F-]
divide by 2 bc x = [ion] / subscript

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

Thermodynamics tells us about the _________ of a chemical reaction, whereas kinetics tells us about the __________ of the reaction.

A

energy, rate

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

If you calculate the reaction rate at t = 0, what rate did you just calculate?

A

instantaneous rate and initial rate

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

Any factors that causes molecules to __________________ speeds up the reaction rate

A

collide more frequently

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

The factors affecting the rates of a chemical reaction

A

Medium or Nature of the Reactants
Concentration (pressures for gases)
Temperature
A catalyst

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

For a reaction that is zero-order overall the rate…

A

does not change during the reaction.

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

Rate will also not change for a ___________ if you double or triple the concentration of reactant.

A

zero-order reaction

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

A catalyst…

A

speeds up the reaction by lowering activation energy but does not change K (equilibrium constant)

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

All else being equal, a reaction with a higher activation energy compared to one with a lower activation energy will…

A

proceed slower.

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

If the exponents in the rate-law do not match the coefficients in the balanced chemical equation, then we know that…

A

the reaction does not take place in one step.

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

Transition states are _______________.

A

short-lived

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

where is the reaction rate the fastest?

A

at the beginning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Reaction Rate

CH3Cl + OH- –> CH3OH + Cl-

rate = ?

A

-∆ [CH3Cl] /∆t = ∆ [CH3OH] /∆t

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Reaction Rate:

A

the change in concentration of one of the reactants of products at a selected stage of the reaction divided by the time interval over which change takes place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

___________ is the reaction rate at a specific moment in time or specific concentration

A

Instantaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

___________ is the reaction rate over a defined time interval

A

Average

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

___________ is a single unique average rate of reaction that is uniform across all reactants and products

A

Unique average reaction rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

The instantaneous rate is the ___________ to the curve at the time of interest

A

slope of the tangent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Most instantaneous rates ___________ as the reaction proceeds.

A

decrease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

The instantaneous rate of reaction at the start of the reaction is called the ____________

A

initial rate of reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

the initial rate always has the unit:

A

concentration/time
rate = M/s (molarity over time)

58
Q

The rate of the reaction depends on the __________ of the two reactants. This expression is known as the ___________.

A

concentrations, rate law

59
Q

Some reaction rates depend heavily on the concentrations of the reactants, while other reaction rates do not. The __________ is the degree to which the reaction rate depends on the concentrations.

A

reaction order

60
Q

Reaction orders can only be

A

0, 1, 2

61
Q

_________ reaction order indicates that something other than concentration is determining rate of reaction.

A

zero

62
Q

The __________ is unique to each rate law. The units depend on the overall order of the reaction.

A

rate constant, k,

63
Q

units for rate constant (k) for zero-order reaction?

A

M x s-1

64
Q

units for rate constant (k) for second reaction order?

A

M-1 x s-1

65
Q

units for rate constant (k) for first reaction order?

A

s-1

66
Q

____________ show concentration as a function of time

A

Integrated rate laws

67
Q

integrated rate law for zero order:

A

[A] = [A]0 - kt
slope of int. rate law plot = -k

68
Q

integrated rate law for first order:

A

ln[A] = ln[A]0 - kt
slope of int. rate law plot = -k

69
Q

integrated rate law for second order:

A

1/[A] = 1/[A]0 + kt
slope of int. rate law plot = k

70
Q

rate law for zero order:

A

rate = k

71
Q

concentration vs. time plot for zero order:

A

negative linear until hits x-axis and trails straight

72
Q

rate law for first order:

A

rate = k[A]

73
Q

concentration vs. time plot for first order:

A

decreases exponentially

74
Q

rate law for second order:

A

rate = k[A]^2

75
Q

concentration vs. time plot for second order:

A

decreases exponentially (drops faster than first order, more concave)

76
Q

empirical rate law

A

rate = k[A]^x [B]^y

77
Q

____________ allows us to predict how long a reaction will take, or how much of the reactant remains after a certain amount of time.

A

Integrated rate laws

78
Q

Half-life is the amount of time it takes for…

A

one half of [A]0 to react away.

79
Q

The amount of reactant remaining after n half-lives is

A

[A] = (1/2)^n [A]0

80
Q

Zero order:
As the concentration decreases, the half-life __________

A

decreases

81
Q

First order:
As the concentration decreases, the half-life __________

A

remains constant

82
Q

Second order:
As the concentration decreases, the half-life __________

A

increases

83
Q

0th order half-life formula

A

t1/2 = [A]0 / 2k

84
Q

1st order half-life formula

A

t1/2 = ln2 / k

85
Q

2nd order half-life formula

A

t1/2 = 1 / k[A]0

86
Q

Radioactive isotopes half-lives are __________ and do not depend on how much material is present

A

constant
first-order half life

87
Q

All radioactive decay is ___________.

A

first-order

88
Q

____________ is a distinct event in the progress of a reaction, often a collision of particles

A

Elementary Reaction

89
Q

___________ is the number of reactant molecules, atoms, or ions in a specific elementary reaction

A

Molecularity

90
Q

Unimolecular =

A

1 reactant

91
Q

Bimolecular =

A

2 reactants

92
Q

Termolecular =

A

3 reactants

93
Q

___________ is a sequence of elementary reactions or steps that take place as reactants are transformed into products

A

Reaction Mechanism

94
Q

An intermediate is ________ early in the mechanism and then _________ later, so it doesn’t appear in the ____________.

A

produced, consumed, overall reaction

95
Q

The rate of the overall reaction is determined by the rate of the ________________. This step is called the ____________ or _______________ step.

A

slowest elementary step, rate limiting step, rate determining step

96
Q

If there is an intermediate in the slow step, you must find a way to ________ the reactant(s) that lead to the production of the intermediate.

A

swap out

97
Q

higher concentration increases the __________ of collisions, resulting in a _________ reaction

A

frequency, faster

98
Q

a solid reactant with a __________ creates offers more opportunities for reaction, so crushing large chunks of a solid into a fine powder results in a ________ reaction.

A

larger surface area, faster
ex. crushed ice melts in drink faster than regular cubed ice

99
Q

reactant molecules have _______ at higher temperatures, so a larger number of reactant molecules can get over the ____________ hump.

A

more energy, activation energy

100
Q

The rate constant k __________ with increasing temperature.

A

increases (exponentially)

101
Q

All reactions go ________ at higher temperatures.

A

faster

102
Q

Arrhenius Law formula

A

k = Ae^-(Ea/RT)

103
Q

The _____________ is the rate constant at infinite temperature, or the theoretical maximum reaction rate possible.

A

pre-exponential factor A

104
Q

_____________ is the minimum amount of energy that the reactants need in order to undergo a chemical reaction.

A

Activation energy Ea

105
Q

The higher the activation energy, the _______ the temperature dependence of the rate constant

A

stronger

106
Q

Low activation energies around 10 kJ/mol

A

temperature “independent”

107
Q

High activation energies around 60 kJ/mol

A

temperature dependent

108
Q

The same reaction at two different temperatures will have two different ___________.

A

rate constants

109
Q

Arrhenius equation:

A

ln (k2/k1) = Ea/R (1/T1 - 1/T2)

110
Q

_________ states that even if all the molecules have sufficient energy, not all interactions between reactants will lead to products.

A

Collision theory

111
Q

On reaction coordinate plot, peaks are _______________

A

transition states or amount of steps in mechanism

112
Q

On reaction-coordinate plot, number of valleys represents number of ___________

A

intermediates

113
Q

If the reaction is endothermic in the forward direction, the activation is higher for the ________ direction than for the ________ direction.

The high Ea means that the rate constant of the ________ reaction depends more strongly on temperature than does the rate constant of the _____ reaction

A

forward, reverse
forward, reverse

114
Q

If the reaction is exothermic in the forward direction, the activation energy is lower for the ________ direction than for the _______ direction.

The low Ea means that the rate constant of the ________ reaction depends more strongly on temperature than does the rate constant of the ________ reaction

A

forward, reverse
reverse, forward

115
Q

For endothermic reactions: when the temperature increases, the _______ rate constant increases more than that of the _________ reaction.

A

forward, reverse

116
Q

For exothermic reactions: when the temperature increases, the _______ rate constant increases more than that of the _______ reaction.

A

reverse, forward

117
Q

If you increase the heat on an exothermic reaction, the ________ start to become more favored.

A

reactants

118
Q

Collision theory only applies to…
Transition State Theory or Activated Complex Theory usually applies to…

A

molecules in the gas phase
molecules in solution

119
Q

An ____________ is an arrangement of two molecules that can either go on to form products or fall apart again into the unchanged reactants.
The _________ have lengthened and weakened.
The ________ are only partly formed.

A

activated complex
original bonds
new bonds

120
Q

In order for a reaction to occur, molecules have to get __________.

This causes their potential energies to increase due to two factors:

A

“too close”

  1. proton-proton repulsions
  2. electron-electron repulsions
121
Q

If the initial KE of the reactants is less than the Ea…

A

no reaction will occur

122
Q

A catalyst is _______ early in the reaction and _________ as a product later. It _______ appear in the overall reaction.

A

consumed, regenerated, does not

123
Q

A catalyst is a compound or material that ________________ for the reactants to become products.

A

opens up a new reaction pathway (a new mechanism)

124
Q

The new pathway has a _______ transition state energy than the original pathway

A

lower

125
Q

The new pathway might have the _______ elementary steps or __________

A

the same number of, it might have more or fewer

126
Q

The catalyst is the only factor that…

A

lowers the activation energy

127
Q

Homogenous catalysts:

A

catalyst that is in the same phase as the reactants

128
Q

Heterogenous catalysts:

A

catalyst that is in a phase different from that of the reactants

129
Q

net ionic equation for the formation of precipitate
Copper (II) phosphate

A

3Cu2+ (aq) + 2PO43- (aq) <=> Cu3(PO4)2 (s)

130
Q

net ionic equation for the formation of precipitate
Silver sulfite

A

Ag2+ (aq) + SO32- (aq) <=> Ag2SO3 (s)

131
Q

net ionic equation for the formation of precipitate
Nickel (II) sulfide

A

Ni2+(aq) + S2- (aq) <=> NiS (s)

132
Q

tin (IV) phosphate

A

Sn3(PO4)4

133
Q

iodate

A

IO3-

134
Q

IO3-

A

iodate

135
Q

cesium (III) iodate

A

Cs(IO3)3

136
Q

to determine what is most or least soluble you can’t just go off ________, you have to __________

A

Ksp values, calculate molar solubility (or ballpark #’s)

137
Q

The overall order of a reaction can be found by…

A

the sum of all the orders of the reactants

138
Q

The reaction order is the relationship between _________ and ___________

A

reactant concentrations, the rate of a reaction

139
Q

For solubility reactions, the dissolved ions are the _________ on the ________. Thus, if Qsp < Ksp, the ions __________.

A

products, right, remain dissolved

140
Q

The Arrhenius equation is often used to compare the rate constants measured at two different temperatures. Using two sets of data points, the equation can be rearranged to yield…

This equation can also be written as…

A

ln(k2/k1) = Ea/R (1/T1 - 1/T2)

ln k = ln A - Ea/RT

141
Q

Therefore if one measures rate constants at many temperatures and constructs a plot of _________ the slope of the plot would be ________ and the intercept will be ________

A

ln k vs 1/T
-Ea/R
ln A