Brainscape's Knowledge GenomeTM

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


See full index

MCAT > GENERAL CHEM > Flashcards

GENERAL CHEM Flashcards

You may prefer our related Brainscape-certified flashcards:
MCAT flashcards
1
Q

what is the mass and charge a proton?

A

mass - approximately 1 atomic mass unit (amu)
charge - +1 e (fundamental unit of charge)

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

what does the atomic number (Z) of an element tell you?

A

the number of protons found in an atom of that element

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

what does the mass number (A) of an atom tell you?

A

it is the sum of the protons and neutrons in the atom’s nucleus

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

what are isotopes?

A

atoms that share an atomic number but have different mass numbers due to a different number of neutrons

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

what convention is used to show both the atomic and mass number of an atom X?

A

A over Z next to X

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

is the electrostatic or gravitational attractive force greater for subatomic particles and why?

A

electrostatic because the masses of subatomic particles are so small

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

do electrons closer to or farther from the nucleus have higher energy?

A

farther

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

what are valence electrons

A

electrons that are farthest from the nucleus
- have strongest interactions with the surrounding environment and weakest interactions with the nucleus
- involved in bonding

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

atomic _____ is nearly synonymous with ______ number. atomic _______ is a _________ average of naturally occurring isotopes of that element

A

mass - mass

weight - weighted

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

what are the units of molar mass

A

g/mol

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

what is the equation for angular momentum

A

L = mvr

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

what is the Planck relation

A

E = hf

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

what is Bohr’s equation for possible values of angular momentum of an electron

A

L = (nh) / 2π

n = principle quantum number

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

what is Bohr’s equation for the energy of an electron

A

E = - RH / n^2

RH = Rydberg unit of energy equal to 2.18 x 10^-18 J/electron

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

when electrons go from a higher to a lower energy state, they _____ photons

A

emit

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

when electrons go from a lower to a higher energy state, they _______ photons

A

absorb

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

what is the equation for the electromagnetic energy of these photons

A

E = (hc) / λ

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

as electrons go from a lower to a higher energy level, they get _______ (mnemonic)

A

AHED
Absorb light
Higher potential
Excited
Distant (from nucleus)

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

what is an electron’s atomic emission spectrum

A

a spectrum of distinct energy levels unique to that element (based on the electrons it contains)
- when electrons drop from an excited state to ground state, they emit photons with wavelengths corresponding to that specific energy transition

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

what is the Lyman series

A

group of hydrogen emission lines corresponding to transitions from energy levels n>/2 to n = 1

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

what is the Balmer series

A

group of hydrogen emission lines corresponding to transitions from energy levels n>/3 to n=2

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

what is the Paschen series

A

group of hydrogen emission lines corresponding to transitions from energy levels n>/4 to n=3

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

the energy of the emitted photon corresponds to the ___________

A

difference in energy between the higher-energy initial state and lower-energy final state

E = (RH)[ 1/ni^2 - 1/nf^2 ]

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

T or F: an electron’s change in energy is the same in between any two energy levels

A

T
- conservation of energy
- the amount of energy absorbed to go higher equals the amount of energy emitted to go lower

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

what is the Heisenberg uncertainty principle

A

it is impossible to simultaneously determine, with perfect accuracy, the momentum and position of an electron
- can’t assess one while not affecting the other

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

what are the four quantum numbers

A

n, l, ml , and ms

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

what is Pauli’s exclusion principle

A

no two electrons in a given atom can possess the same set of four quantum numbers

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

what is the maximum number of electrons within a shell

A

2n^2

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

the difference in energy between two electron shells decreases as the distance from the nucleus __________

A

increases

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

for any principal quantum number n, there will be n possible values for l, ranging from 0 to ______

A

n - 1

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

what is the azimuthal quantum number

A

l
- tells you the shape and number of subshells within a given shell

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

what is spectroscopic notation

A

shorthand representation of principal and azimuthal quantum numbers
- L = 0 –> s
- L = 1 –> p
- L = 2 –> d
- L = 3 –> f

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

what is the maximum number of electrons within a subshell

A

4l + 2

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

what is the magnetic quantum number

A

ml
- Specifies the particular orbital within a subshell where an electron is most likely to be found

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

the possible values of ml are the integers between ________

A

-l and +l , including 0

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

for any value of l, there will be __________ possible values of ml
for any n, this produces _______ orbitals
for any n, there will be a maximum of _______ electrons

A

2l + 1
n^2
2n^2 (two per orbital)

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

what is the spin quantum number

A

ms
- tells you the spin of the electron
- two possible values, +1/2 and -1/2

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

electrons with opposite spins are said to be _________ and must be in ________ orbitals

A

paired ; different

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

electrons with the same ms value are said to have _________

A

parallel spins

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

what is the aufbau principle

A

electrons fill from lower to higher energy subshells and each subshell will fill completely before electrons begin to enter the next one

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

what is the n + l rule

A

rule for ranking subshells by increasing energy
- the lower the sum of n + l, the lower the energy of the subshell
- if the sum for two shells is equal, the shell with the lower n value has a lower energy

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

what is Hund’s rule

A

within a given subshell, orbitals are filled such that there are a maximum number of half-filled orbitals with parallel spins

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

what are paramagnetic materials

A

materials composed of atoms with unpaired electrons and will orient their spins in alignment with a magnetic field

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

what are diamagnetic materials

A

materials consisting of atoms that have only paired electrons and thus are slightly repelled by a magnetic field

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

which elements only have paired electrons

A

elements that come at the end of a block

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

which elements violate aufbau

A

chromium, copper, and silver

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

what is the periodic law

A

the chemical and physical properties of the elements are dependent, in a periodic way, upon their atomic numbers

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

periods are ______ and groups/families are ________

A

rows ; columns

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

periods graphically represent the ________ and groups help to determine the ________

A

principal quantum number ; valence electron configuration

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

what are the representative elements

A

elements that have their valence electrons in either s or p subshells

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

what are the nonrepresentative elements

A

the transition elements and the lanthanide and actinide series

51
Q

where are metals found on the periodic table

A

left side and middle
- include the first two groups (except H), transition elements and the lanthanide and actinide series

52
Q

what are the properties of metals

A

they are lustrous (shiny), malleable/ductile, have high melting points, and good conductors of electricity

53
Q

T or F: metals easily give up electrons

A

T

54
Q

what are the properties of nonmetals

A

dull, poor conductors of electricity, and brittle

55
Q

where are nonmetals found in the periodic table

A

upper right side starting with carbon and then diagonal staircase down to Rn

56
Q

where are metalloids found in the periodic table

A

diagonal staircase down from boron to Po and At

57
Q

what are the periodic trends from left to right

A

atomic radius decreases, ionization energy increases, electron affinity increases, electronegativity increases

58
Q

what is a zeroth-order reaction and what is its rate law

A

a reaction whose rate is independent of concentration
rate = k

59
Q

what is a first-order reaction and what is its rate law

A

a reaction whose rate is directly proportional to the concentration of one of the reactants
rate = k[A]

60
Q

what is a second-order reaction and what is its rate law

A

a reaction that either depends on the square of the concentration of one product or on concentrations of both products
- for square one - rate = k[A]^2

61
Q

what does the Arrhenius equation show

A

the effect of temperature change on rate constant and thus rate of reeaction

62
Q

what do you need in an amino acid side chain for a pi-stacking interaction

A

an aromatic ring

63
Q

what do you need in an amino acid side chain for a salt bridge to form?

A

a charged side group that is the opposite charge of what it’s forming the salt bridge with

64
Q

what does the Hill coefficient tell you

A

cooperativity
- a Hill coefficient greater than 1 is positive cooperativity
- a fractional coefficient (less than 1) is negative cooperativity
- a coefficient equal to 1 is no cooperativity

65
Q

what is Ki

A

inhibition constant
- concentration of the inhibitor at which the reaction rate is half of the maximum reaction rate

66
Q

pyrrole is a _____

A

five-membered aromatic heterocycle containing 1 nitrogen atom
- C4H5N

67
Q

what is Boyle’s law

A

if temperature and amount of gas remain constant, the absolute pressure exerted by a gas is inversely proportional to its volume
P1V1 = P2V2
P = 1/V

68
Q

what is Charles’s law

A

when pressure is constant, the Kelvin temperature and volume are proportional to each other
V1/T1 = V2/T2

69
Q

T or F: steroids are nonhydrolyzable lipids

A

T

70
Q

how many isoprene units and fused rings do steroids have

A

6 ; 4

71
Q

what is an esterase

A

enzyme that hydrolyzes particular esters into acids and alcohols or phenols
- RCOOH + R’OH

72
Q

what is an amidase

A

enzyme that hydrolyzes acid amides usually with the liberation of ammonia
- RC(=O)NHR’ –> RCOOH + R’NH2

73
Q

what is a phosphatase

A

an enzyme that removes a phosphate group from a protein

74
Q

what is Hess’s Law

A

the heat of a reaction will sum and be the same no matter what
- even if you break it into tiny steps, it will release or absorb the same amount of heat by the end

75
Q

what is the chemical formula of formate

A

conjugate base of formic acid (HCOOH)
- HCOO-

76
Q

what is the chemical formula of carbonate

A

CO3 (2-)

77
Q

what is the chemical formula of bicarbonate

A

HCO3-

78
Q

what is the chemical formula of acetate

A

CH3CO2
C2H3O2

79
Q

anion-exchange chromatography separates out proteins with ______ while cation-exchange chromatography separates out proteins with ______

A

negative charges (these are the ones that bind to the resin surface) ; positive charges

anion exchange has a positive resin that the negative molecules stick to ; cation exchange has a negative resin that the positive molecules stick to

80
Q

what is the heat of fusion

A

the amount of energy required to convert a solid to a liquid (melting ice)

81
Q

what is the function of a protein kinase

A

catalyzes the transfer of a phosphate (specifically y-phosphate from ATP) to other substrates

82
Q

what are the three labels for the three phosphates in ATP

A

a, B, and gamma

83
Q

what is the oxidation number of H

A

+1
- unless it’s with something more electropositive (like in NaH it’s -1)

84
Q

what is the oxidation number of O

A

-2
- unless it’s in a peroxide (H2O2, Na2O2) in which case it’s -1

85
Q

what are the oxidation numbers of diatomic species (H2, N2, etc)

A

always 0

86
Q

T or F: ions always have the same oxidation numbers as their charges

A

T
oxidation number of Ca is 2 as it is 2+

87
Q

what is the oxidation state of N in NH4+

A

-3
4H means + 4 ; + charge means there’s a +1 left over

88
Q

how many liters does 1 mol of gas occupy at STP?

A

22.4 L

89
Q

standard conditions vs STP

A

standard conditions - 25˚C, 298.15 K, 24L of gas

STP - 0˚C, 273K, 22.4L of gas

90
Q

Which of the following oxidative transformations is unlikely to occur?

A.A primary alcohol to an aldehyde
B.A tertiary alcohol to a ketone
C.An aldehyde to a carboxylic acid
D.A secondary alcohol to a ketone

A

B.A tertiary alcohol to a ketone

91
Q

what’s the difference between a primary and secondary alcohol

A

primary alcohol - hydroxyl group is connected to primary carbon (only connected to one other carbon)

secondary alcohol - hydroxyl group is connected to secondary carbon (connected to 2 carbons)

92
Q

how to tell if something is Z or E configuration

A

Z - high priority groups are on the same side of the double bond

E - high priority groups are on the opposite side of the double bond

93
Q

what’s the IUPAC procedure for naming something?

A

By IUPAC rules, first identify the longest unbroken chain of carbon atoms. Next, number the carbon atoms in this chain starting from the end that gives C=C the lowest numbers. The double bond is identified by the position of the carbon atom from the lowest numbered end (2), and then the methyl group is assigned at the 3-position. The stereochemical designator for the double bond is Z because the highest priority groups (methyl at C2 and ethyl at C3) occur on the same side of the double bond. The name is therefore Z-3-methylpent-2-ene. (specific example)

94
Q

Two vectors of magnitudes |A| = 8 units and |B| = 5 units make an angle that can vary from 0° to 180°. The magnitude of the resultant vector A + B CANNOT have the value of:

A.2 units.
B.5 units.
C.8 units.
D.12 units.

A

A. 2 units

smallest value is 3 units when they have an angle of 180˚ between them and largest value is 13 units when they have 0˚ between them

95
Q

what are the equations for electric field

A

E = V/d
F = qE
E = kq/r^2

96
Q

1 Hz is also equal to _____

A

cycles per second

97
Q

Group 1 elements are called _____ and Group 2 elements are called ______

A

alkali metals ; alkaline earth metals

98
Q

a double bond contains what kind of bonding interactions

A

one sigma, one pi

99
Q

what is sublimation

A

phase change from solid to gas

100
Q

what is the critical point on a pressure-temperature graph

A

the point where the liquid and gaseous phase merge together as a single phase

101
Q

what is an imine

A

functional group containing a carbon-nitrogen double bond

102
Q

what is a carbamate

A

both an amide and ester; a nitrogen atom of the amide and oxygen atom of the ester share a carbonyl group

103
Q

what is an imidazole

A

five-membered heterocyclic system that has both an -NH- and -N=

104
Q

what are lactones

A

cyclic carboxylic esters

105
Q

which reducing agent is stronger: LiAlH4 or NaBH4

A

LiAlH4 - can be used on esters, carboxylic acids, and acid amides

NaBH4 (weaker) - only aldehydes and ketones

106
Q

what is an acetal

A

has structure R1O–CR2R3–OR4 where R1 and R4 are carbon groups and R3 and R2 are a carbon and a H

107
Q

T or F: hydroxide can hydrolyze esters (and open up lactone rings)

A

T ; adds an H to the ester

108
Q

hydrolysis vs condensation reactions

A

hydrolysis - use water to break molecule into smaller molecules ; break bonds and water is added to remaining fragments

condensation - smaller molecules combine to form larger molecules with the loss of a water

109
Q

what is characteristic of ping-pong substrate binding mechanism

A

no ternary complex is formed
- also called double-displacement

110
Q

what is ordered vs random-order substrate binding mechanism

A

ordered - TP substrate binds first without any catalysis occurring and then dNTP

random order - either substrate could bind first

111
Q

what is the buffering capacity of a buffer

A

+/- 1 pH unit away from the pKa

112
Q

The electric field inside each of the conductors that forms the capacitor in the defibrillator is zero. Which of the following reasons best explains why this is true?

A.All of the electrons in the conductor are bound to atoms, and thus there is no way for an external electric field to penetrate atoms with no net charge.
B.Free electrons in the conductor arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field.
C.Free electrons in the conductor arrange themselves on the surface and throughout the interior so that the electric field they produce inside the conductor exactly cancels any external electric field.
D.All electrons in the conductor, both free and bound, arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field.

A

B.Free electrons in the conductor arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field.

Conductors contain both atom-bound electrons and free electrons. Free electrons arrange themselves on the surface of conductors, and their collective electric field produced inside the conductor cancels any external electric field. The resulting electric field inside the conductor is zero.

113
Q

what is osmotic pressure

A

the diffusion of solvent across a semipermeable membrane from a solution of lower concentration to one of higher concentration during osmosis creates osmotic pressure

P = iMRT

i = van’t Hoff index ; M = concentration ; R = gas constant ; T=temperature

114
Q

what is the electron configuration for Fe2+?

the configuration for neutral Fe is 1s2 2s2 2p6 3s2 3p6 4s2 3d6

A

1s2 2s2 2p6 3s2 3p6 3d6

  • the two electrons were taken from the 4s subshell bc it is the highest shell
115
Q

what does it mean when orbitals are degenerate

A

they have the same energy

116
Q

when ligands cause a difference in energy of orbitals, this can result in _______

A

the absorption of different wavelengths of light

  • example: hemoglobin is red when bound to O2 bc it interacts with heme’s d orbitals
117
Q

what is a coordinate covalent bond

A

bond between a central atom and a ligand where the ligand donates both of the electrons involved

118
Q

what is the coordination number

A

the number of coordinate bonds to the central atom

119
Q

anode is the site of _________ and cathode is the site of __________

A

oxidation ; reduction

120
Q

what is the definition of an intermediate

A

a transient chemical species that is produced in one elementary step and consumed in a subsequent step

121
Q

what are the changes associated with gamma decay

A

mass number: +0
atomic number: +0
elemental identity is unchanged
a gamma ray (high-energy photon) is released

122
Q

what are the changes associated with B- decay

A

mass number: +0
atomic number: +1
a neutron converts to a nuclear proton and emits an electron and an antineutrino

123
Q

what are the changes associated with B+ decay

A

mass number: +0
atomic number: -1
a nuclear proton converts to a neutron and ejects a positron and a neutrino

124
Q

what are the changes associated with electron capture E (a form of B decay)

A

mass number: +0
atomic number: -1
a proton captures an electron near the nucleus and converts a neutron without any emission

MCAT (10 decks)

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