MCAT CORE MAIN EXAM UPDATED QUESTIONS AND
ANSWERS SURE A+
✔✔ionic compound - ✔✔a compound composed of positive and negative ions but has
no net charge overall
✔✔beta decay - ✔✔-radioactive decay in which an electron is emitted (a neutron is
converted to a proton and an electron is emitted)
-*Mass Number stays the same and atomic number increases by 1*
-faster than alpha particles and penetrate further, can pass through paper, but not an
aluminum sheet. Negatively charged
✔✔gamma decay - ✔✔radioactive decay by emission of a gamma ray, no change in
mass number or atomic number
✔✔chiral - ✔✔sp3 hybridized, attached to 4 different groups
✔✔formula for number of sterioisomers - ✔✔2^n
✔✔Boiling chips and vacuum distillation, respectively, are used in distillations to: - ✔✔
✔✔chemical extractions - ✔✔used to separate compounds based on different
solubilities
✔✔Distillation - ✔✔A process that separates the substances in a solution based on their
boiling points
✔✔Recrystallization - ✔✔Used to purify chemicals. By dissolving both impurities and a
compound in an appropriate solvent, either the desired compound or impurities can be
coaxed out of solution, leaving the other behind.
✔✔Chromatography - ✔✔A technique that is used to separate the components of a
mixture based on the tendency of each component to travel or be drawn across the
surface of another material. Based on the affinity to the column.
✔✔Centrifugation - ✔✔Separates components by density using high speed spinning.
more dense particles travel to the bottom.
✔✔At the end of a distillation, the compound remaining in the original flask will be -
✔✔the one with higher boiling point
✔✔boiling points of aldehyde - ✔✔300 C
✔✔boiling points of carboxylic acids - ✔✔170 C
,✔✔Boiling points & melting pts of alkanes and alkenes - ✔✔low
✔✔Due to hydrogen bonding, alcohols and carboxylic acids have ___ melting/boiling
points than aldehydes and ketones and can function as organic weak ___. - ✔✔higher;
acids
✔✔A mass of 10 kg is dropped from a height of 20 m. Ignoring air resistance, what is
the maximum speed it achieves?
What formulas would you use to solve this? - ✔✔PE = mgh
KE = 1/2(m)v^2
✔✔A mass of 10 kg is dropped from a height of 20 m. Ignoring air resistance, what is
the maximum speed it achieves? - ✔✔PE = mgh
PE = 10kg * 10 m/s^2 * 20 m
PE = 2000 kg/s^2 = 2000 J
KE = 1/2*10kg v^2 = 2000 J
v = sqrt(400) = 20 m/s
✔✔stereocenter - ✔✔sp3, bonded to 4 different substituents
✔✔The preferred ion configuration of many elements on the periodic table is
determined by: - ✔✔the tendency of elements to gain or lose electrons until they have
the same electron configuration as the nearest noble gas
✔✔equation for torque - ✔✔τ = F∙d∙sin(θ)
-F is the force applied
-d is the distance that the force is applied from the fulcrum
-θ is the angle between the lever arm and the force that is applied
✔✔sin 90° - ✔✔1
✔✔For an anterior force of 98 N and a torque of 13 Nm, what is the distance from which
force was applied? Given force was applied perpendicular to rotation - ✔✔T = r F
sin(theta)
Perpendicular so theta = 90 degrees, sin theta = 1
13 Nm = r (98N) (1)
r = 13 Nm/98N
r = 0.133 m
or r = 133 mm
✔✔What unit is torque measured in? - ✔✔Nm (Newtons * meters)
,✔✔how many mm are in 1 meter? - ✔✔1000
✔✔torque is caused by - ✔✔force applied to a lever arm at a certain distance from an
object capable of rotating, known as a fulcrum
✔✔three ways to increase the torque applied to an object - ✔✔(1) increasing the force,
(2) increasing the distance at which the force is applied from the fulcrum, and (3)
adjusting the angle at which the force is applied to make it as close as possible to
perpendicular to the lever arm.
✔✔velocity - ✔✔distance/time (m/s)
✔✔If a 90-kg man undergoes a turning acceleration of 5 m/s2 during a running turn,
what is the magnitude of force experienced by the foot due to the ground? - ✔✔990 N
To turn while running, the foot must push off the ground, which applies a shearing force
while simultaneously supporting the weight of the body.
We must account for the normal force exerted by the ground on the foot. This is a
verticle force which occurs as a result of the runner's weight. We must also consider the
acceleration force since direction is changing. This force is horizontal. These two force
vectors are perpendicular and will form a right triangle.
Fnormal = mg = 90 kg(10) = 900 N
Fturning = 90(5) = 450
a^2 + b^2 = c^2
c = sqrt(900^2 + 450^2)
c = 90(10^2 + 5^2)^1/2
c = 90(125)^1/2
c = 90*11 = 990 N
✔✔equivalence point of a titration - ✔✔on a graph, it is the point with vertical line
✔✔If the equivalence point of a titration with catopril is when 7.5 mL of 2*10^-2 M of
NaOH is a added, How many moles of captopril were present in the original analyte
solution tested? - ✔✔# moles = M * V = 2*10^-2 mol/liter * 7.5mL /1000mL = 1.5*10^-4
mol NaOH
since this is equivalence point, the mols NaOH will equal mols Catopril, so answer is
1.5*10^-4 mol * 1000 mmol/1mol = 0.15 mmol
✔✔At equivalence points during the titration - ✔✔the number of acid or base groups
added to the solution is equivalent to the number of base/acid groups in the original
unknown solution
, ✔✔formula to calculate unknown concentration - ✔✔m1*v1 = m2*v2
✔✔competitive inhibition Km and Vmax - ✔✔Km increases, Vmax stays the same
✔✔if environmental ph is lower than pka, the molecule will in it's ____ form -
✔✔deprotonated
✔✔IC50 - ✔✔concentration of inhibitor required to reduce enzyme activity by 50%
✔✔the lower the IC50 value, the ____ inhibitor required to achieve a certain effect, the
lowest IC50 should correspond to the conditions where inhibitory activity is ____ -
✔✔less; greatest
✔✔Newton's Third Law - ✔✔F(A on B) = -F(B on A)
✔✔Newton's 2nd Law of Motion - ✔✔Fnet=ma
✔✔Newton's First Law of Motion - ✔✔Fnet = 0 at equilibrium
✔✔Nitrogen is primarily present in the atmosphere as a diatomic gas. Which of the
following is true about this form of nitrogen? - ✔✔Diatomic nitrogen gas is relatively inert
and can be used in the atmosphere in laboratory reactions to prevent unwanted side
reactions.
✔✔Which of the following is closest to the bond angle between the carbon atoms in a
molecule of acetone? - ✔✔120 degrees (trigonal planar)
✔✔acetone structure and formula - ✔✔C3h6O
✔✔A circuit is constructed with a 12-V battery and four identical resistors, each with a
resistance of 16 Ω, and connected in parallel. What is the total power dissipated by the
circuit? - ✔✔36 W
1. Find total resistance:
1/Rtot = 1/16 + 1/16 + 1/16 + 1/16
1/Rtot = 4/16 = 1/4
Rtot = 4 ohms
2. Solve for power:
P = V^2/R = 12^2/4 = 144/4 = 36 W
✔✔3 power formulas - ✔✔P = IV
P = I^2R
ANSWERS SURE A+
✔✔ionic compound - ✔✔a compound composed of positive and negative ions but has
no net charge overall
✔✔beta decay - ✔✔-radioactive decay in which an electron is emitted (a neutron is
converted to a proton and an electron is emitted)
-*Mass Number stays the same and atomic number increases by 1*
-faster than alpha particles and penetrate further, can pass through paper, but not an
aluminum sheet. Negatively charged
✔✔gamma decay - ✔✔radioactive decay by emission of a gamma ray, no change in
mass number or atomic number
✔✔chiral - ✔✔sp3 hybridized, attached to 4 different groups
✔✔formula for number of sterioisomers - ✔✔2^n
✔✔Boiling chips and vacuum distillation, respectively, are used in distillations to: - ✔✔
✔✔chemical extractions - ✔✔used to separate compounds based on different
solubilities
✔✔Distillation - ✔✔A process that separates the substances in a solution based on their
boiling points
✔✔Recrystallization - ✔✔Used to purify chemicals. By dissolving both impurities and a
compound in an appropriate solvent, either the desired compound or impurities can be
coaxed out of solution, leaving the other behind.
✔✔Chromatography - ✔✔A technique that is used to separate the components of a
mixture based on the tendency of each component to travel or be drawn across the
surface of another material. Based on the affinity to the column.
✔✔Centrifugation - ✔✔Separates components by density using high speed spinning.
more dense particles travel to the bottom.
✔✔At the end of a distillation, the compound remaining in the original flask will be -
✔✔the one with higher boiling point
✔✔boiling points of aldehyde - ✔✔300 C
✔✔boiling points of carboxylic acids - ✔✔170 C
,✔✔Boiling points & melting pts of alkanes and alkenes - ✔✔low
✔✔Due to hydrogen bonding, alcohols and carboxylic acids have ___ melting/boiling
points than aldehydes and ketones and can function as organic weak ___. - ✔✔higher;
acids
✔✔A mass of 10 kg is dropped from a height of 20 m. Ignoring air resistance, what is
the maximum speed it achieves?
What formulas would you use to solve this? - ✔✔PE = mgh
KE = 1/2(m)v^2
✔✔A mass of 10 kg is dropped from a height of 20 m. Ignoring air resistance, what is
the maximum speed it achieves? - ✔✔PE = mgh
PE = 10kg * 10 m/s^2 * 20 m
PE = 2000 kg/s^2 = 2000 J
KE = 1/2*10kg v^2 = 2000 J
v = sqrt(400) = 20 m/s
✔✔stereocenter - ✔✔sp3, bonded to 4 different substituents
✔✔The preferred ion configuration of many elements on the periodic table is
determined by: - ✔✔the tendency of elements to gain or lose electrons until they have
the same electron configuration as the nearest noble gas
✔✔equation for torque - ✔✔τ = F∙d∙sin(θ)
-F is the force applied
-d is the distance that the force is applied from the fulcrum
-θ is the angle between the lever arm and the force that is applied
✔✔sin 90° - ✔✔1
✔✔For an anterior force of 98 N and a torque of 13 Nm, what is the distance from which
force was applied? Given force was applied perpendicular to rotation - ✔✔T = r F
sin(theta)
Perpendicular so theta = 90 degrees, sin theta = 1
13 Nm = r (98N) (1)
r = 13 Nm/98N
r = 0.133 m
or r = 133 mm
✔✔What unit is torque measured in? - ✔✔Nm (Newtons * meters)
,✔✔how many mm are in 1 meter? - ✔✔1000
✔✔torque is caused by - ✔✔force applied to a lever arm at a certain distance from an
object capable of rotating, known as a fulcrum
✔✔three ways to increase the torque applied to an object - ✔✔(1) increasing the force,
(2) increasing the distance at which the force is applied from the fulcrum, and (3)
adjusting the angle at which the force is applied to make it as close as possible to
perpendicular to the lever arm.
✔✔velocity - ✔✔distance/time (m/s)
✔✔If a 90-kg man undergoes a turning acceleration of 5 m/s2 during a running turn,
what is the magnitude of force experienced by the foot due to the ground? - ✔✔990 N
To turn while running, the foot must push off the ground, which applies a shearing force
while simultaneously supporting the weight of the body.
We must account for the normal force exerted by the ground on the foot. This is a
verticle force which occurs as a result of the runner's weight. We must also consider the
acceleration force since direction is changing. This force is horizontal. These two force
vectors are perpendicular and will form a right triangle.
Fnormal = mg = 90 kg(10) = 900 N
Fturning = 90(5) = 450
a^2 + b^2 = c^2
c = sqrt(900^2 + 450^2)
c = 90(10^2 + 5^2)^1/2
c = 90(125)^1/2
c = 90*11 = 990 N
✔✔equivalence point of a titration - ✔✔on a graph, it is the point with vertical line
✔✔If the equivalence point of a titration with catopril is when 7.5 mL of 2*10^-2 M of
NaOH is a added, How many moles of captopril were present in the original analyte
solution tested? - ✔✔# moles = M * V = 2*10^-2 mol/liter * 7.5mL /1000mL = 1.5*10^-4
mol NaOH
since this is equivalence point, the mols NaOH will equal mols Catopril, so answer is
1.5*10^-4 mol * 1000 mmol/1mol = 0.15 mmol
✔✔At equivalence points during the titration - ✔✔the number of acid or base groups
added to the solution is equivalent to the number of base/acid groups in the original
unknown solution
, ✔✔formula to calculate unknown concentration - ✔✔m1*v1 = m2*v2
✔✔competitive inhibition Km and Vmax - ✔✔Km increases, Vmax stays the same
✔✔if environmental ph is lower than pka, the molecule will in it's ____ form -
✔✔deprotonated
✔✔IC50 - ✔✔concentration of inhibitor required to reduce enzyme activity by 50%
✔✔the lower the IC50 value, the ____ inhibitor required to achieve a certain effect, the
lowest IC50 should correspond to the conditions where inhibitory activity is ____ -
✔✔less; greatest
✔✔Newton's Third Law - ✔✔F(A on B) = -F(B on A)
✔✔Newton's 2nd Law of Motion - ✔✔Fnet=ma
✔✔Newton's First Law of Motion - ✔✔Fnet = 0 at equilibrium
✔✔Nitrogen is primarily present in the atmosphere as a diatomic gas. Which of the
following is true about this form of nitrogen? - ✔✔Diatomic nitrogen gas is relatively inert
and can be used in the atmosphere in laboratory reactions to prevent unwanted side
reactions.
✔✔Which of the following is closest to the bond angle between the carbon atoms in a
molecule of acetone? - ✔✔120 degrees (trigonal planar)
✔✔acetone structure and formula - ✔✔C3h6O
✔✔A circuit is constructed with a 12-V battery and four identical resistors, each with a
resistance of 16 Ω, and connected in parallel. What is the total power dissipated by the
circuit? - ✔✔36 W
1. Find total resistance:
1/Rtot = 1/16 + 1/16 + 1/16 + 1/16
1/Rtot = 4/16 = 1/4
Rtot = 4 ohms
2. Solve for power:
P = V^2/R = 12^2/4 = 144/4 = 36 W
✔✔3 power formulas - ✔✔P = IV
P = I^2R
