Brainscape's Knowledge GenomeTM

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


See full index

AAMC Specific Cards > Chem + Phys > Flashcards

Chem + Phys Flashcards

1
Q

half-life

A

the time it takes for half of all the radioactive nuclei to decay into their daughter nuclei

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

Which phosphate is used by kinases to transfer phosphoryl groups?

A

the γ-phosphate of ATP

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

Pressure of air

A

Pair = P + ρv^2 / 2

P=static pressure

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

Venturi Effect

A

the reduction in fluid pressure when a fluid flows through a constricted section

When velocity goes up, pressure goes down

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

Why do G-C base pairs have higher melting points?

A

G–C base pairs form stronger π-stacking interactions than A–T base pairs, thereby creating the most thermal stability.

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

sphingolipids

A

participate in tissue development, cell recognition and adhesion, and act as receptors for toxins

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

Coordinate covalent bond

A

one atom supplies all of the electrons

vs. covalent where two atoms are sharing

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

How will adding a strong acid to a solution effect equilibrium?

A

Look at which molecules may become protonated/deprotonated (will therefore be decreased in solution)

Then, look at how Le Chat may impact equilibrium

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

Coordination number

A

of molecules that bind to another molecule

ex. in [Cu(NH3)4]2+, 4 indicates the coordination number of Cu

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

Which elements will have small second ionization energies?

A

Second Ionization energy is the energy required to remove a two electrons.

Alkaline earth metals (per 2) will have the smallest ionization energies because their charge is 2+, so removing two will make them stable like a noble gas

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

When two values have a decibel difference of 20, what is the ratio of intensities?

A

The difference is 20 dB, meaning that the decimal log of the ratio of their intensities is 2, which means that the ratio of their intensities is 100

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

A negative focal length will be…
converging/diverging?
virtual/real?
enlarged/reduced?

A

diverging, virtual, reduced

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

Which energy conversions best describes what takes place in a battery-powered resistive circuit when the current is flowing?

A

Chemical to electric to thermal

the chemical energy of the battery elements is used as electrical energy to set the charge carriers in motion through the resistor, where they experience drag from the crystal lattice of the resistive conductor and dissipate their energy as heat from the resistor

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

Difference between phospholipid and triaglyceride

A

phospholipids have a charged head group in addition to three fatty acids ester linked to a single glycerol

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

Will polar compounds increase or decrease the boiling point of a molecule?

A

increase (increased hydrogen bonding, harder to break)

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

How does a boiling chip prevent superheating?

A

Introduce small air bubbles into system.

The air bubbles break the surface tension of the liquid being heated and prevent superheating and bumping.

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

Which experimental modification will improve the degree of separation in a fractional distillation?

A

lengthening the column or heating the flask at a slower rate (allow both liquids more time in the fractionating column (increase the number of theoretical plates, allowing liquid and vapor to equilibrate))

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

What happens to vapor pressure when temperature increases?

A

The vapor pressure of a liquid increases with increasing temperature.

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

What happens to the boiling point of a liquid when the pressure on the surface is decreased?

A

the boiling point of a liquid decreases as the pressure on the surface is decreased

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

How would you find the number of ions?

A

Start with grams then use molar mass to convert to moles.
Once you have moles use mole ratio to make sure number is accurate
Multiply by avogadro’s number 6.02 x 10^23

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

What would happen to litmus paper if dipped in a solution of Na2Co3 and water?

A

sodium carbonate is a water soluble salt. Will dissolve and create hydroxide

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

How do increased intramolecular forces impact an acid?

A

Increased intramolecular forces (H bonding) create a stronger acid

for strong acids, you want a weak (stable) conjugate base

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

Is a carbonyl or an alcohol more polar?

A

alcohol!

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

What impacts first ionization energy?

A

How easy it is to remove an electron. A full octet will make it challenging to remove electrons & will be highest at top right corner

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

The acid catalysis in a substitution reaction typically acts to do what?

A

create a better leaving group

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

The formula for the number of possible peptides that contain one each of n amino acids is

A

n! (n factorial)

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

How to figure out ionic character

A

Elements that have very different electronegativities will have higher ionic character

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

How is diamond made?

A

from carbon under pressure

graphite are stacked sheets of carbon

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

Is O-H ionic?

A

no it’s covalent

H bonds are intermolecular forces- they are not ionic bonds

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

Under what conditions do gasses deviate from the ideal gas law?

A

at low temperatures and high pressures

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

When does pH = pka?

A

When the acid and conjugate base concentrations are equal, the pH of a buffer equals the pKa of the acid.

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

Will Na2+ react with water?

A

no- sodium ions are soluble and inert

however, a nitrite ion NO2- is likely to be hydrolyzed- after they receive H, OH will be left, increasing pH

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

Mutarotation

A

change in optical rotation due to change in equilibrium between two anomers

34
Q

Reduction is an increase/decrease in the number of bonds between C and H

A

increase

35
Q

low dielectric constant

A

low ability to store electrical energy

36
Q

What distinguishes between an “α” and “β”

A

Stereochemistry at the anomeric carbon (C bonded to 2 Os)

37
Q

What would be a likely explanation for a triacylglycerol creating 4 fatty acids?

A

One of the three fatty acid units may have isomerized (both cis and trans isomers produced)

38
Q

Are fatty acids soluble in polar or nonpolar solvents?

A

Both- A fatty acid salt contains a long hydrocarbon chain, which is soluble in nonpolar solvents. The salt also contains the charged group –CO2–Na+, which is soluble in polar solvents.

39
Q

Why does nitrogen not react?

A

because of the very strong triple bond

40
Q

Why will the concentration of H2O sometimes be emitted from the equilibrium equation?

A

The amount/concentration of a liquid will not change during a reaction; it will be fairly stable

41
Q

What will happen when Ca is added to water?

A

Will become Ca2+

Ca(s) + 2H2O(l) → Ca2+(aq) + 2OH–(aq) + H2(g)

42
Q

Ionization energy

A

refers to the amount of energy required to remove an electron

43
Q

empirical formula

A

gives the relative number of atoms of each element it contains.

44
Q

What is the maximum volume of PH3(g) that a chemist can obtain from the reaction shown by Equation 1a, if 0.005 mol LiPH2 reacts with 0.002 mol R2NBCl2 at 0oC and 1 atm?

2 R2NBCl2 + 5 LiPH2 → 4 LiCl + 3 PH3 + Intermediate

A

Since 3 moles of PH3 are produced, and each mol will occupy 22.4 L

(conditions from problem indicate .003 moles, so .003x22.4=67.2)

45
Q

Will a heavier object have more or less moles?

A

less; one gram sample will contain FEWER moles

46
Q

How to figure out ionization constant?

A

Strong acids that dissociate well would have a high ionization constant (high Ka)

Weak acids that dissociate a little bit will have a small ionization constant (low Ka)

47
Q

In the Bohr model of the atom, radiation is emitted whenever electrons:

A

move to orbits of lower energy

48
Q

M(OH)2 has a molar solubility of S mol/L at 25°C. Its Ksp value is:

A

4S^3

The Ksp for a substance, AaBb, equals [A]a[B]b.

The Ksp for M(OH)2 = [M][OH–]^2. If the solubility of M(OH)2 is S mol/L, then [M] = S mol/L and [OH–] = 2S mol/L.

The Ksp = S(2S)^2 = S(4S^2) = 4S^3.

49
Q

When finding partial pressure, remember to…

A

balance the equation!!! and in general

50
Q

Why do precipitates form?

A

Because the Ksp ([A]a[B]b) is exceeded, precipitate will form to maintain the Ksp

51
Q

How to find oxidation state

A

by subtracting assigned electrons from their periodic group number

ex. Carbon is at its lowest oxidation state when it is CH4 (Cannot be reduced)

52
Q

Does one mole occupy a volume of 22.4 at 25 degrees celsius and 1 atm pressure

A

no! STP is 0 degrees celsuis- the rest is correct

53
Q

Flavin

A

3 rings with nitrogens

54
Q

ubiquinone

A

two rings with carbonyls and long hydrophobic chain

55
Q

What is required for a molecule to be polar?

A

Cannot be linear or have cancelling dipoles

56
Q

How does density change probability of fusion?

A

if density increases, probability of fusion does as well

57
Q

How does the distance between fuel particles change the probability of fusion?

A

The probability of fusion increases with the decrease in the average distance between fuel particles that enables attractive nuclear forces to overcome the repelling nuclear forces acting at medium and long distances

58
Q

continuity equation for flow

A

vπ r^2 = vπ r^2

59
Q

Where will a lipophilic compound be found?

A

in the hydrophobic layer- not the aqueous

60
Q

How to find the Ki value?

A

Ki is the concentration of the inhibitor at which the reaction rate is half of the maximum reaction rate

61
Q

pka and acid

A

a low pka indicates a strong acid

62
Q

What is the pressure formula?

A

pressure = force / area

division!! not multiplication

63
Q

How to calculate charge in a capacitor?

A

q = CV

C in farads
V in volts

64
Q

What are the units of capacitance?

A

farads

65
Q

How is capacitance related to the distance between parallel plates?

A

C is inversely proportional to the separation d between the parallel plates

A decrease in the separation corresponds to an increase in the capacitance.

(C =(ϵ0 ϵr A)/d)

66
Q

What is the impact of removing a dielectric on capacitance?

A

Removing the dielectric essentially means decreasing the permittivity ϵr to 1, which corresponds to a decrease in the capacitance.

(recall C =(ϵ0 ϵr A)/d)

67
Q

What is the impact of decreasing the area of parallel plates on capacitance?

A

Because the capacitance is directly proportional to the area of the parallel plates, a decrease in the area corresponds to a decrease in the capacitance.

68
Q

Should a reaction be in equilibrium when using Michaelis mentin?

A

no, if a reaction is in equilibrium, the measurement of V0 will be impossible to obtain and the kinetic data will be the same, regardless of substrate conc.

we want to be able to affect the rate of reaction by changing substrate conc.

also, you need the initial rate/velocity, which is not attainable at equilibrium

69
Q

ΔG′°

A

ΔG′° = −RTlnKeq

Keq= [P]/[R]

70
Q

pK

A

pK is the pH at which the fraction of folded DNA is 0.5

71
Q

ionization energy

A

the more stable atom with the less electrons will have the highest ionization energy because it will hold onto its electrons the tightest

ex. fluorine will have higher first ionization than iodine

same trend as electronegativity

72
Q

volume flow rate equation

A

Q=vA

v=velocity
A=area

73
Q

What will dilute slowest in an SDS page?

A

the largest molecule

the smallest will dilute fastest

74
Q

A protein with a large charge will require what to elute?

A

a high concentration of NaCl

75
Q

If a light enters a medium with higher density, how will it bend?

A

toward the normal (perpendicular) line

76
Q

How will an electron move towards an cathode?

A

it will accelerate

note: electrons typically travel anode to cathode

77
Q

What are the charges on the plates of a capacitor?

A

they will be equal and opposite

78
Q

Do you need the distance between the source and observer to determine the doppler effect?

A

no; need old frequency, velocity in a medium, velocity of the object, velocity of the source

79
Q

In the law of mass action, what state is excluded?

A

pure solids and liquids

an equilibrium constant expression involves a ratio of products to reactants with exponents determined from the stoichiometry of the reaction.

80
Q

How many sigma and pi bonds are in a triple bond?

A

2 pi bonds, 1 sigma bond

81
Q

Where are free electrons located in a conductor when the electric field is 0?

A

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.

AAMC Specific Cards (3 decks)

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