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.