AAMC MCAT Practice Exam 1EXAM NEWEST 2025
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+
If a solution containing the B) Methyl-2-butene
compounds shown in
Figure 4, is injected into a The answer to this question is B because 2-methyl-2-
gas-liquid chromatograph, butene will exhibit the lowest molecular weight and
the first peak observed in also the weakest intermolecular forces of attraction.
the gc trace is attributable This substance will therefore migrate the fastest and
to which compound? be the first peak in the gas chromatograph (gc) trace.
A) Methyl-2-butanol
B) Methyl-2-butene
C) Chloro-2-methylbutane
D) Bromo-2-mehtylbutane
R = clockwise
R vs. S stereochemistry*
C = counter-clockwise
B) increases V = IR
When the current in the
The answer to this question is B because according to Ohm's law, current is
micro-robot's circuit
equal to voltage divided by resistance. If current increases and resistance is
increases and the resistance constant, then voltage increases as well.
of the circuit remains
constant, the voltage of the
circuit:
A) decreases
B) increases
C) is constant
D) is zero
,Acetic acid and ethanol D) Replace the hydroxyl oxygen of ethanol with O-18.
react to form an ester
product as shown below. The answer to this question is D because this
experiment involves labeling a group which does not
In determining which exchange with other groups present prior to reaction
reactant loses the -OH and will therefore give information about the true
group, which of the identity of the groups, which are exchanged during
following isotopic the reaction.
substitutions would be
most useful?
A) Replace the acidic H of
acetic acid with D
B) Replace the alcoholic H
of ethanol with D.
C) Replace the carbonyl
oxygen of acetic acid with
O-18.
D) Replace the hydroxyl
oxygen of ethanol with O-
A person whose eye has a C) 51 D
lens-to-retina distance of
2.0 cm, can only clearly The answer to this question is C because the strength
see objects that are closer of the eye lens is equal to the inverse of the focal
than 1.0 m away. What is length of the eye lens. Its numerical value is given by
the strength S of the (1 m)-1+(0.02 m)-1=1 D+50 D=51 D.
person's eye lens? (Note:
Use the thin lens formula
1/O + 1/I = S)
A) -50 D
B) -10 D
C) 51 D
D) 55 D
,Which statement correctly D) the transition state changes the activation energy
describes how enzymes of the reaction.
affect chemical reactions?
Stabilization of: The answer is D because the stabilization of the
transition state, not the substrate, provides binding
A) the substrate changes energy that is used to lower the activation energy.
the free energy of the
reaction.
B) the transition state
changes the free energy
of the reaction.
C) the substrate changes
the activation energy of
the reaction.
D) the transition state
changes the activation
energy of the reaction.
Which of the following will C) Adding concentrated HCl (aq)
decrease the percentage
ionization of 1.0 M acetic The answer to this question is C because HCl is a
acid, CH3CO2H(aq)?* strong acid that will increase the amount of H+ in
solution and thus decrease the percentage of
A) Chlorinating the CH3 CH3CO2H that ionizes.
group
B) Diluting the solution
C) Adding concentrated
HCl (aq)
D) Adding a drop of basic
indicator
, Knowing that the speed of B) 1.4
light in the vitreous humor
is 2.1 × 108 m/s, what is the n = c/v
index of refraction of the
vitreous humor? (Note: The answer to this question is B because the index of
The speed of light in a refraction of a medium is equal to the ratio of the
vacuum is 3.0 × 108 m/s.) speed of light in vacuum to the speed of light in the
A) 0.7 medium, thus it is equal to (3.0 x 108 m/s)/(2.1 x 108
B) 1.4 m/s) = 1.4.
C) 2.1
D) 3.0
The intensity of the D) number of photons emitted
radiation emitted by the
oxygen sensor is directly The answer to this question is D because the energy
proportional to the: of electromagnetic radiation is directly proportional
to the number of photons, and the intensity of
A) propagation speed of electromagnetic radiation is defined as energy
the radiation emitted per unit time. Thus, intensity is directly
B) wavelength of the proportional to the number of photons emitted.
radiation
C) polarization of photons
emitted
D) number of photons
emitted
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+
If a solution containing the B) Methyl-2-butene
compounds shown in
Figure 4, is injected into a The answer to this question is B because 2-methyl-2-
gas-liquid chromatograph, butene will exhibit the lowest molecular weight and
the first peak observed in also the weakest intermolecular forces of attraction.
the gc trace is attributable This substance will therefore migrate the fastest and
to which compound? be the first peak in the gas chromatograph (gc) trace.
A) Methyl-2-butanol
B) Methyl-2-butene
C) Chloro-2-methylbutane
D) Bromo-2-mehtylbutane
R = clockwise
R vs. S stereochemistry*
C = counter-clockwise
B) increases V = IR
When the current in the
The answer to this question is B because according to Ohm's law, current is
micro-robot's circuit
equal to voltage divided by resistance. If current increases and resistance is
increases and the resistance constant, then voltage increases as well.
of the circuit remains
constant, the voltage of the
circuit:
A) decreases
B) increases
C) is constant
D) is zero
,Acetic acid and ethanol D) Replace the hydroxyl oxygen of ethanol with O-18.
react to form an ester
product as shown below. The answer to this question is D because this
experiment involves labeling a group which does not
In determining which exchange with other groups present prior to reaction
reactant loses the -OH and will therefore give information about the true
group, which of the identity of the groups, which are exchanged during
following isotopic the reaction.
substitutions would be
most useful?
A) Replace the acidic H of
acetic acid with D
B) Replace the alcoholic H
of ethanol with D.
C) Replace the carbonyl
oxygen of acetic acid with
O-18.
D) Replace the hydroxyl
oxygen of ethanol with O-
A person whose eye has a C) 51 D
lens-to-retina distance of
2.0 cm, can only clearly The answer to this question is C because the strength
see objects that are closer of the eye lens is equal to the inverse of the focal
than 1.0 m away. What is length of the eye lens. Its numerical value is given by
the strength S of the (1 m)-1+(0.02 m)-1=1 D+50 D=51 D.
person's eye lens? (Note:
Use the thin lens formula
1/O + 1/I = S)
A) -50 D
B) -10 D
C) 51 D
D) 55 D
,Which statement correctly D) the transition state changes the activation energy
describes how enzymes of the reaction.
affect chemical reactions?
Stabilization of: The answer is D because the stabilization of the
transition state, not the substrate, provides binding
A) the substrate changes energy that is used to lower the activation energy.
the free energy of the
reaction.
B) the transition state
changes the free energy
of the reaction.
C) the substrate changes
the activation energy of
the reaction.
D) the transition state
changes the activation
energy of the reaction.
Which of the following will C) Adding concentrated HCl (aq)
decrease the percentage
ionization of 1.0 M acetic The answer to this question is C because HCl is a
acid, CH3CO2H(aq)?* strong acid that will increase the amount of H+ in
solution and thus decrease the percentage of
A) Chlorinating the CH3 CH3CO2H that ionizes.
group
B) Diluting the solution
C) Adding concentrated
HCl (aq)
D) Adding a drop of basic
indicator
, Knowing that the speed of B) 1.4
light in the vitreous humor
is 2.1 × 108 m/s, what is the n = c/v
index of refraction of the
vitreous humor? (Note: The answer to this question is B because the index of
The speed of light in a refraction of a medium is equal to the ratio of the
vacuum is 3.0 × 108 m/s.) speed of light in vacuum to the speed of light in the
A) 0.7 medium, thus it is equal to (3.0 x 108 m/s)/(2.1 x 108
B) 1.4 m/s) = 1.4.
C) 2.1
D) 3.0
The intensity of the D) number of photons emitted
radiation emitted by the
oxygen sensor is directly The answer to this question is D because the energy
proportional to the: of electromagnetic radiation is directly proportional
to the number of photons, and the intensity of
A) propagation speed of electromagnetic radiation is defined as energy
the radiation emitted per unit time. Thus, intensity is directly
B) wavelength of the proportional to the number of photons emitted.
radiation
C) polarization of photons
emitted
D) number of photons
emitted
