Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chem 2 final > Definitely on the Test > Flashcards

Definitely on the Test Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

le chatelier’s principle

A

if a reaction in equilibrium is disturbed, the reaction shifts left in order to minimize the disturbance

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

acid equilibrium expression

A

K(a) = [H3O+][A-]/[HA]

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

rate and temperature

A

higher temp. = higher rxn rate because there will be more collisions (need correct orientation)

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

units for rate laws (1st order)

A

s ^-1

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

spontaneity

A

the tendency to occur without being driven by an external force

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

entropy

A

energy and matter tend to disperse in an orderly manner

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

predicting change in entropy

A
  1. phase change (s - l +S; l - q +S, q - l -S)
  2. state of matter (solid < liquid < gas)
  3. atomic weight (He < Ne < Ar < Kr, Xe)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

enthalpy & ∆S

A

if ∆H is - (exothermic) ∆S increases
if ∆H is + (endothermic) ∆S decreases

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

∆S equation

A

∆S = ∆S(final) — ∆S(inital) [J/K or J/Kmol]

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

direction of chemical change

A

entropy helps us determine the direction a rxn will proceed in (direction that increases entropy of the universe)

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

second law of thermodynamics

A

for any spontaneous process, the entropy of the universe increases (∆S > 0)

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

∆S and ∆H

A

entropy is more important than enthalpy at certain temps

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

equation for entropy of the universe

A

∆S(universe) = ∆S(system) + ∆S(surroundings)

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

temperature effect on ∆S

A

entropy depends on temperature
magnitude of ∆S(surr) is proportional to ∆H(sys)

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

equation for temperature effect on ∆S

A

∆S(surr) = -∆Hsys/T

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

equation for gibbs free energy

A

∆G(sys) = ∆H(sys) - T∆S(sys)

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

gibbs free energy

A

∆G is a value that can tell us about the spontaneity of a reaction

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

gibbs and spontaneity

A

if ∆G is + , ∆S(uni) is — (nonspontaneous)
if ∆G is - , ∆S(unis) is + (spontaneous)

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

STP

A

25° C, 1 atm, 1.0 M

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

∆S° equation

A

∆S°(rxn) = ∑n∆S(products) — ∑n∆S(reactants)

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

∆G° equation

A

∆G°(rxn) = ∑n∆G(products) — ∑n∆G(reactants)

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

entropy for an element

A

∆S° is NOT 0!

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

calculating ∆G at non-standard conditions

A

∆G = ∆G° + RTlnQ

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

calculating ∆G at equilibrium

A

∆G° = -RTlnK

∆G° = K @ equilibrium

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

intermolecular forces (ion-ion)

A

essentially an ionic bond (not an IMF) [opposites attract]

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

intermolecular forces (ion-dipole)

A

charged ions are attracted to the opposite “partial charge” on a nearby polar molecule [STRONGEST]

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

intermolecular forces (hydrogen)

A

dipole-dipole interaction involving “H” atoms. [2nd STRONGEST]
rule to form hydrogen IMF:
1. H must be bonded to F, O, or N
2. H is attracted to a lone electron pair

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

intermolecular forces (dipole-dipole

A

partial positive & negative charges on polar molecules attract [3rd STRONGEST]

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

intermolecular forces (london dispersion)

A

induced dipole moment. depends on the molecular weight of the molecule. More weight = stronger LD force. (all molecules have LD forces) [4th STRONGEST]

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

how a liquid boils

A

it undergoes a phase change (all imf forces must be broken)

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

phase change (L - G)

A

vaporization (boiling)

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

phase change (L - S)

A

freezing

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

phase change (S - G)

A

sublimation

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

phase change (G - L

A

condensation

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

phase change (S - L)

A

melting

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

phase change (G - S)

A

deposition

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

vapor pressure and temperature

A

as temp. increases, so does vapor pressure

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

boiling point

A

the temp. where vapor pressure of has is equal to atmospheric pressure

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

equilibrium

A

the rate of the forward reaction is equal to the rate of the reverse reaction

(concentrations of reactants/products stay constant)

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

equilibrium constant (K)

A

K = [products]/[reactants]

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

equilibrium constant (K) extra info

A

K depends on temperature and nature of reactants

pure liquids and solids are not involved in the expression

K is unitless

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

reverse of a chemical rxn

A

K(reverse) = 1/K

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

multiplying rxn by a factor

A

K^factor

44
Q

adding two rxns

A

K(overall) = K(1) * K(2)

45
Q

K and pressure

A

K is large (> 1) [Pro] > [Reac] rxn lies to the right [ΔG -]

K is small (< 1) [Pro] < [Reac] rxn lies to the left [ΔG +]

46
Q

factors that change equilibrium (volume)

A

V increases (P decreases) rxn shifts left

V decreases (P increases) rxn shift right

47
Q

factors that change equilibrium (temperature) [exothermic]

A

[adding product] rxn shifts left

[removing product] rxn shifts right

48
Q

factors that change equilibrium (temperature) [endothermic]

A

[adding reactant] rxn shifts right

[removing reactant] rxn shifts left

49
Q

strong acid

A

an acid that dissociates completely into ions solution

50
Q

strong base

A

a base that reacts completely with H+ ions in solution.

51
Q

weak acid

A

an acid that is only slightly dissociated in solution

52
Q

weak base

A

A base that does not completely react with H+ ions in solution.

53
Q

base equilibrium expression

A

K(b) = [OH-][HB+]/[B]

54
Q

large K(a)

A

acid is relatively strong weak acid (weak conjugate base)

55
Q

small K(a)

A

acid is relatively weak weak acid (strong conjugate base)

56
Q

K(w) equation

A

K(w) = K(a) * K(b)

57
Q

auto ionization of water

A

K(w) = [H3O+][OH-] = 1.0x10^-14

58
Q

template for weak acid rxn

A

HA + H2O ⇄ H3O+ + A-

59
Q

template for weak base rxn

A

B + H2O ⇄ OH- + HB+

60
Q

K(a) and pK(a)

A

pK(a) = -log[Ka]

K(a) = 10^-pKa

61
Q

pH and pOH

A

pH = -log(H+) [H3O+]

pOH = -log(OH-)

14 = pH + pOH

62
Q

pH scale

A

ph > 7 basic

pH = neutral

ph < 7 acidic

63
Q

list of strong acids

A

HCl, HBr, HI,

H2SO4

HClO4

HNO3

64
Q

list of strong bases

A

LiOH, NaOH, KOH,

Ca(OH)2, Sr(OH)2, Ba(OH)2

65
Q

buffer solution

A

a buffer is a solution that resists a change in pH when a strong acid/base is added, or if the solution is diluted

66
Q

henderson - hasselbalch equation

A

easy way to calculate pH of buffer

pH = pKa + log [A-]/[HA]

Ka = Kw/Kb

67
Q

titrations

A

a controlled chemical rxn that is used to calculate the concentration of an unknown substance

68
Q

oxidation

A

the loss of electrons (OIL)

69
Q

reduction

A

the gain of electrons (RIG)

70
Q

rules for redox reactions

A

both oxidation and reduction must occur

of e- lost must = # of e- gained

71
Q

rules for balancing redox reactions

A
  1. break the reaction into two half rxns
  2. balance all atoms other than O and H
  3. add H2O to balance O atoms
  4. add H+ to balance H atoms

a. if in acid go to step 5

b. if in base, add OH- to both sides

  1. add e- to correct side to balance
  2. multiply half rxns to get e- equal
  3. add the two half rxns
72
Q

galvanic (voltaic) cell

A

redox rxn that is always spontaneous (E +) [G-]

73
Q

salt bridge

A
  1. each rxn is separated into a half cell
  2. e- transfer occurs at electrodes (solids)
  3. ions move through solution
  4. oxidation occurs at the anode
  5. reduction occurs at the cathode
  6. salt bridge connects the two cells and allows charge to flow between solutions
74
Q

direction of ions/e- in salt bridge (galvanic)

A

e- flow FROM anode TO cathode

NO3- flows into anode solution

K+ flows into cathode solution

anode solution goes into metal

cathode metal goes to cathode solution

75
Q

calculating e cell

A

E°cell = E°red — E°ox (in V)

76
Q

e° cell at equilibrium

A

E°cell = (0.0592/n) * logK

77
Q

nernst equation

A

used when not at equilibrium

E = E° — (0.0592/2) * logQ

78
Q

what does nernst equation mean?

A

Q > 1 (Ecell decreases) [rxn shifts left]

Q = 1 (ΔE = 0V)

Q < 1 (Ecell increases) [rxn shifts right]

79
Q

electrolytic cell

A

a nonspontaneous electric cell which requires a potential greater than E°cell to drive the rxn

80
Q

anode + cathode (electrolytic)

A

anode is +

cathode is —

[reduction still happens at cathode]

81
Q

electrical current

A

current is the flow of charge

82
Q

current (i)

A

i = charge / time

83
Q

ampere

A

coulomb / second

84
Q

what factors affect rxn rates (physical state of matter)

A

gas = slow

liquid = faster

solid = fastest

85
Q

what factors affect rxn rates (conc. of reactants)

A

higher [conc.] = fast

lower [conc.] = slow

86
Q

what factors affect rxn rates (temp.)

A

higher temp. = fast

lower temp. = slow

87
Q

what factors affect rxn rates (presence of catalyst)

A

catalysts speed up the reaction

88
Q

rxn rate

A

R = Δ[conc] / Δt

89
Q

rxn rate of reactant

A

R = — Δ[reactants] / Δt

90
Q

rxn rate of product

A

R = + Δ[products] / Δt

91
Q

general rate of rxn

A

aA + bB = cC

R = (-1/a)Δ[A]/Δt = (-1/b)Δ[B]/Δt = +(1/c)*Δ[C]/Δt

92
Q

rate laws

A

rate = k[A]^m [B]^n

93
Q

what rate constant (k) means

A

large k = FAST

small k = SLOW

94
Q

activation energy

A

the minimum amount of energy required to start a chemical reaction (break bonds)

95
Q

Ea (exothermic)

A

final potential energy is lower than starting energy

96
Q

Ea (endothermic)

A

final potential energy is higher than starting energy

97
Q

arrhenius equation

A

k=Ae^(-Ea/RT)

98
Q

single step rxn mechanism

A

reaction occurs in a single step

2 molecules = bimolecular

3 molecules = termolecular

4 molecules = quad-molecular

99
Q

multi-step rxn mechanism

A

rxn happens in multiple steps

(will have an intermediate species that doesn’t appear in the overall rxn)

100
Q

orders of multi-step rxns

A

A = product (1st order)

A + B = product (2nd order)

A + A = product (2nd order)

A + A + B = product (3rd order)

101
Q

catalyst

A

substance that speeds up the rate of a chemical reaction by lowering the activation energy (is not used up in the reaction) [will appear in the beginning and end of reaction but not in the overall]

102
Q

integrated rate law (0th order)

A

[A]t — [A]0 = -kt

103
Q

integrated rate law (1st order)

A

ln[A]t — ln[A]0 = -kt

104
Q

integrated rate law (2nd order)

A

1/[A]t — 1/[A]0 = kt

105
Q

units for rate laws (0th order)

A

M / s

106
Q

units for rate laws (2nd order)

A

1 / M * s

107
Q

units for rate laws (1st order)

A

s^-1

Chem 2 final (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions