AAMC 1 Chem/Phys Flashcards
In chromatography, what would determine the relative rate of migration of the various components?
The relative rate of migration of the various components will depend on the amount of hydrogen bonding to the stationary phase.
If both fumaric and maleic is acid are produced from the dehydration of malic acid it tells you that?
It tells me that the dehydration of malic acid is NOT stereospecific.
What functional group is formed during the formation of a peptide bond?
The group that forms during a peptide bond formation is a an Amide group.
If 1-pentanol is replaced by 2-pentanol the rate of a substitution reaction changes in what way and why?
The rate of substitution in protonated alcohols is subject to steric hindrance changing a primary OH to a secondary one will decrease the rate of the reaction (substitution)
If a solution containing a variety of compounds, the first peak observed is the go trace will be attributable to?
In gas chromatography compounds with lower boiling point, smaller/lighter in molecular weight, will show first in the chromatogram.
The very first peaks are often the solvent, however
The compound with the lowest molecular weight and the weakest intermolecular forces of attraction. This will make the migration faster and make it the first peak in the gas chromatography.
2-methyl-2-butene will show first than 2-bromo-2-methylbutane
Gas chromatography compounds are often run with a reference that allows ball park estimation of the compound and it is coupled with other analytical tools such as mass spectrometry
In gas chromatography the area underneath the peak is directly related to?
In gas chromatography the area underneath each peak is directly proportional to the amount of compound in the mixture.
What formula do you use to calculate the strength of a persons eye’s lens?
Calculate it for a person with lens to retina distance of 2cm that can only see objects that are 1m away.
The thin lens formula is S= 1/O+1/I
The formula is the inverse of the foal length of the eye lens.
1D+50D= 51D
In enzyme kinetics the stabilization of?
The transition state provides binding energy that is used to change (lower) the activation energy of a reaction.
Adding what to an acid will decrease the percentage of ionization of a weak acid?
Adding a strong acid like HCl will decrease the percentage that ionizes from the other acid by increasing the amount of H+ in solution.
If current in a circuit increases and the resistance of the circuit remains the same, the voltage of the circuit?
INCREASES.
According to Ohm’s law, current is equal to voltage divided by resistance, so (I= V\R) if the current increases and the resistance is constant then voltage increases as well.
How do yo calculate the index of refraction of a medium?
If the speed of light in the medium is 2.1•10^8 m/s
The index of refraction of a medium is equal to the ration of the speed of light in a vacuum tot he speed of the light in the medium.
So 3•10^8/2.1•10^8= 1.4 no units
How is the energy of electromagnetic radiation measured?
The energy of electromagnetic radiation is directly proportional to the number of photons, and the INTENSITY of electromagnetic radiation is defined as the energy emites per unit time. The intensity is directly proportional to the number of photons emitted.
What fraction of compound X will decay in 12 minutes if it has a half life of 3 minutes?
The fraction that will decay in 12 minutes if the half life is 3 minutes is 12/3= 4 1/2^4 = 16\16-1/16 is equal to 15/16
What are the units for Watts?
The units for Watts are joules/seconds
Disulfide bond formation is made by the formation of what kind of bond?
It is made by covalent bond formation.
What feature of a molecule is or are responsible for the pH dependence of aggregation?
Side chains whose net charge respond to pH such as acidic side chains that are neutral at low pH. This inhibit aggregation due to electrostatic principles.
Why is the velocity of blood flow slower in capillaries than in arteries?
Because the total (net) cross-sectional area of capillaries exceeds that of arteries.
In a graph showing the relationship between solution pH and applied potential. Lines that are horizontal or perpendicular means?
That the compound is at equilibrium at either pH (horizontal) or Voltage (perpendicular), for both (diagonal)
Hybridization of 5 bonds? 6?
d^2sp^3 for six alpha bonds and dsp^3 for 5 bonds
What are the assumptions made when referring to a gas as, “ideal gas”?
The properties of an “ideal” gas is that it is composed of particles that have negligible volume and do not exert intermolecular forces.
The production of variety of opsins functions to?
The wavelength of light absorbed by a molecule depends on its structure, and so the production of a variety of structurally related opsins functions to enable the detection of different colors.
A compound made of Carbon and hydrogen will make it largely?
Hydrophobic
When thinking of kinases think of ?
When thinking of co-factors think of?
Kinases should bring phosphate to mind is the source of phosphates inorganic or from ATP?
Cofactors are enzyme helpers that contain a METAL.
What reaction is catalizador by an enzyme like LipA?
LipA is a lipase, which means it hydrolyze fatty acids.
The following mutations occurred R33G, K112D, M134D, Y139C, I157M what is the change in NET charge?
1-0, 1-(-1), 0-(-1), 0-0, 0-0
Initially 2 at the end -2 NET difference-4
What kind of sugar is present in UDP?
Ribose. UDP contains Uridine which is a nucleic acid used in RNA, and RNA contains ribose.
What is the action of the laforin?
Laforin is an enzyme that removes phosphate from glycogen.
What happens during the radioactive decay known as b-1?
Carbon is converted into what? For example
During b-1 radioactive decay a neutron is converted into a proton.
A carbon would be converted into a nitrogen.
The amount of what type of bond is decreased in Lafora bodies?
The lack of branching is a characteristic of Lafora bodies. Branching occurs through an alpha-1,6-glycosidic bond in glycogen
A convex (converging) lens will give you what sign in your answer? What about a concave (diverging)?
A concave will give you a psotive sign and a diverging concave will give you a negative sign.
Magnification formula is equal to?
Magnification formula is M= -distance of image/ distance of object or -height of image/ height of object
See picture, and Object is at a distance of three focal lengths from the center of a convex lens. What is the ratio of the height of the image to the height of the object?
Write it on a piece of paper.
You will need the thin lens equation and the magnification equation
Thin lens equation: 1/O+1/i= 1\f
Magnification equation: -or +i/O
Object distance: 3f, focal length:f image distance: i
Answer should be 1/2
Gamma decay occurs when a nucleous emits?
By definition gamma decay means the emission of photons by the nucleus, known as gamma rays
Spontaneous reaction should have?
A negative change in G and a positive S for entropy, as the compound goes from liquid to gas.
If a homogenous catalyst cannot be removed from the products then?
If a homogenous catalyst cannot be removed from the products at the end of a reaction then the products will be contaminated with the catalyst.
How will the rate of a catalyze reaction be affected if the solid catalyst is finely ground before it is added to the reaction?
The rate will be faster because there will be an increase in the amount of catalyst by the increased surface area the catalyst will be exposed to, increasing the rate.
What is an effective way of increasing a current by two?
According to ohms law the current is equal to the voltage divided by the resistance. I=V/R So if the resistance is halved the current should increase by two. The voltage could also be multiplied by two.
If a compound that is a solid and a compound that is a liquid (cation) are mixed and a new compound is formed it is reasonable to say that?
If the liquid (when solid) evolves when placed in an acid, what is reasonable to say about the original solid compound when added to the acid.
That the solid is more susceptible to oxidation that the liquid. Since the liquid was reduced into a solid that cannot be ionized.
It is reasonable to say that it will evolve as well
What volume of .120Moles solution would contain .078 moles of solute?
Do it in a piece of paper
Answer should be 650mL
If deletions in a microsatellite on an intron cause an Exon to be omitted from the final mRNA what does it suggest about the microsatellite?
It would suggest that the microsatellite contains sequences that influence splicing such as an splice acceptor site.
What is the function of a chaperone protein?
What is the function of a chaperone protein?
A protein that facilitates proper folding and inhibits the formation of nonfictional protein aggregates such as heat shocked proteins are an example of chaperone proteins.
