MCAT Section Tests Dear Future Doctor, The following Section Test and explanations should be used to practice and to assess your mastery of critical thinking in each of the section areas Topics are confluent and are not necessarily in any specific order or fixed proportion This is the level of integration in your preparation that collects what you have learned in the Kaplan classroom and synthesizes your knowledge with your critical thinking Simply completing the tests is inadequate; a solid understanding of your performance through your Score Reports and the explanations is necessary to diagnose your specific weaknesses and address them before Test Day All rights are reserved pursuant to the copyright laws and the contract clause in your enrollment agreement and as printed below Misdemeanor and felony infractions can severely limit your ability to be accepted to a medical program and a conviction can result in the removal of a medical license We offer this material for your practice in your own home as a courtesy and privilege Practice today so that you can perform on test day; this material was designed to give you every advantage on the MCAT and we wish you the best of luck in your preparation Sincerely, Albert Chen Executive Director, Pre-Health Research and Development Kaplan Test Prep © 2003 Kaplan, Inc All rights reserved No part of this book may be reproduced in any form, by Photostat, microfilm, xerography or any other means, or incorporated into any information retrieval system, electronic or mechanical without the written permission of Kaplan, Inc This book may not be duplicated, distributed or resold, pursuant to the terms of your Kaplan Enrollment Agreement Physical Sciences Test Time: 35 Minutes Number of Questions: 27 MCAT PHYSICAL SCIENCES DIRECTIONS: Most of the questions in the following Physical Sciences test are organized into groups, with a descriptive passage preceding each group of questions Study the passage, then select the single best answer to each question in the group Some of the questions are not based on a descriptive passage; you must also select the best answer to these questions If you are unsure of the best answer, eliminate the choices that you know are incorrect, then select an answer from the choices that remain Indicate your selection by blackening the corresponding circle on your answer sheet A periodic table is provided below for your use with the questions PERIODIC TABLE OF THE ELEMENTS H 1.0 He 4.0 Li 6.9 Be 9.0 B 10.8 C 12.0 N 14.0 O 16.0 F 19.0 10 Ne 20.2 11 Na 23.0 12 Mg 24.3 13 Al 27.0 14 Si 28.1 15 P 31.0 16 S 32.1 17 Cl 35.5 18 Ar 39.9 19 K 39.1 20 Ca 40.1 21 Sc 45.0 22 Ti 47.9 23 V 50.9 24 Cr 52.0 25 Mn 54.9 26 Fe 55.8 27 Co 58.9 28 Ni 58.7 29 Cu 63.5 30 Zn 65.4 31 Ga 69.7 32 Ge 72.6 33 As 74.9 34 Se 79.0 35 Br 79.9 36 Kr 83.8 37 Rb 85.5 38 Sr 87.6 39 Y 88.9 40 Zr 91.2 41 Nb 92.9 42 Mo 95.9 43 Tc (98) 44 Ru 101.1 45 Rh 102.9 46 Pd 106.4 47 Ag 107.9 48 Cd 112.4 49 In 114.8 50 Sn 118.7 51 Sb 121.8 52 Te 127.6 53 I 126.9 54 Xe 131.3 55 Cs 132.9 56 Ba 137.3 57 La * 138.9 72 Hf 178.5 73 Ta 180.9 74 W 183.9 75 Re 186.2 76 Os 190.2 77 Ir 192.2 78 Pt 195.1 79 Au 197.0 80 Hg 200.6 81 Tl 204.4 82 Pb 207.2 83 Bi 209.0 84 Po (209) 85 At (210) 86 Rn (222) 87 Fr (223) 88 Ra 226.0 89 Ac † 227.0 104 Rf (261) 105 Ha (262) 106 Unh (263) 107 Uns (262) 108 Uno (265) 109 Une (267) * 58 Ce 140.1 59 Pr 140.9 60 Nd 144.2 61 Pm (145) 62 Sm 150.4 63 Eu 152.0 64 Gd 157.3 65 Tb 158.9 66 Dy 162.5 67 Ho 164.9 68 Er 167.3 69 Tm 168.9 70 Yb 173.0 71 Lu 175.0 † 90 Th 232.0 91 Pa (231) 92 U 238.0 93 Np (237) 94 Pu (244) 95 Am (243) 96 Cm (247) 97 Bk (247) 98 Cf (251) 99 Es (252) 100 Fm (257) 101 Md (258) 102 No (259) 103 Lr (260) GO ON TO THE NEXT PAGE as developed by Physical Sciences Passage I (Question 1–6) An accelerometer is a device that may be used to measure the acceleration of an object moving horizontally One type of accelerometer consists of a simple pendulum made up of a small dense body of mass M suspended from a “massless” rod The unweighted end of the rod is fixed, but is allowed to pivot freely about the point P as shown below When the system is accelerated to the right, the pendulum swings back toward the left, and makes an angle θ with the vertical The size of this angle θ gives a measure of the acceleration, so the larger the angle, the greater the acceleration When there is no displacement from the vertical, the system is traveling with a constant velocity Assuming that there are no limitations on the maximum allowable acceleration, what is the maximum angle that the pendulum can make with the vertical? A B C D 90° Slightly less than 90° Slightly greater than 90° 180° The system is moving horizontally to the right such that the pendulum makes an angle of 2° clockwise from the vertical Two seconds later the pendulum swings suddenly to the right, now making an angle of 2° counterclockwise from the vertical Which of the following graphs could represent the velocity of the system during this period? Which of the following equations correctly defines the acceleration of the accelerometer as a function of the angle? This system, however, is very susceptible to small fluctuations in the acceleration, so the pendulum must be provided with some form of damping to attenuate these fluctuations In many cases, the pendulum is suspended in a liquid, such as mineral oil, which has a density of one-eighth the density of the pendulum weight The viscosity of the oil has a damping effect on the swinging of the pendulum This damping does not entirely prevent the pendulum from swinging in response to an acceleration, but rather increases the amount of time that it takes to respond This makes the pendulum less sensitive to these jerky fluctuations (Note: In the accompanying problems, assume that the system is not damped unless otherwise stated and that the acceleration is positive when directed from left to right.) A B C D a = Mg cos θ a = g cot θ a = g tan θ a =v2/r GO ON TO THE NEXT PAGE KAPLAN MCAT A passenger takes a reading each second of the total distance the car has traveled since starting If the accelerometer reads a constant, positive value for seconds, which of the following could be the values for total distance traveled over the four seconds? A 4m, 8m, 12m, 16m B 1m, 4m, 9m, 16m C 4m, 4m, 4m, 4m D 10m, 16m, 21m, 24m Passage II (Questions 7–12) The following reaction and potential energy diagram apply to a gaseous reaction that is measured at standard temperature and pressure in a closed vessel This reaction normally takes place in the atmosphere where it is catalyzed by certain elements of acid smog 2A + B 2C + D Reaction Figure A pendulum rod of length L with a bob of mass M oscillates at a frequency f in a non-accelerating system If the length of the pendulum is doubled, what is the ratio of the new period of oscillation to the old one? A 2:1 B 1: C 2:1 D 1:1 If the pendulum discussed in the passage is suspended in mineral oil, what is the tension in the pendulum rod when the system is at rest? A B Mg C (1/8)Mg D (7/8)Mg The reaction has been found to take place in two steps, the first slow, which follows second-order kinetics, and the second fast The forward reaction occurs spontaneously even without a catalyst The reactants and products behave like ideal gases Changes in equilibrium not affect the phases of the species involved Which energy values could be altered by the introduction of a catalyst? A B C D only and only and only 1, 2, 3, 4, and Which of the following correctly links stressor and response? A An increase in temperature will increase the concentrations of C and D B Decreasing the pH will increase the concentrations of C and D C Removing D as it is formed will increase the concentration of C D An increase in pressure will increase the concentration of A and B GO ON TO THE NEXT PAGE as developed by Which of the following CANNOT be the mechanism for the rate-determining step of this reaction? A A molecule of A collides with a molecule of B B A molecule of A collides with another molecule of A C A molecule of B collides with another molecule of B D Two molecules of A collide with a molecule of B 10 From the information provided in the passage, which of the following can be shown to be true? A B C D Keq> ∆Gf° > The forward reaction is endothermic The potential energy of A is greater than the potential energy of D 11 All of the following statements concerning the activation energy of this system are true EXCEPT: Within the human range of hearing, the sensitivity of the ear varies with frequency That is, the ear is more sensitive to sounds at some frequencies than at others The faintest sound that the ear can detect at any frequency is known as the threshold of hearing This can be seen more clearly in the graph below Also shown on the graph is a line that represents the threshold of pain or feeling; this is the point at which the sensation of hearing changes to that of discomfort, or even pain For a young adult, this threshold is at approximately 120 dB The intensity, I, of a traveling wave is the average rate per unit area at which energy is transported across a perpendicular surface In other words, the intensity is the power transported per unit area, and is expressed in units of W/m2 Because the ear is sensitive over a large range of intensities, it is much more convenient to speak of intensity in terms of sound or intensity level β, defined as: β = 10 log I I0 where I0 is the reference intensity which is chosen to be 10–l2 W/m2, near the lower limit of human audibility (Note: The surface area of a sphere is 4? r2, where r is the radius of the sphere.) A it is the energy necessary to allow the particles to react B its value is reduced by a catalyst C for the reaction to occur spontaneously, it must be less than the potential energy of the reactants D it is not proportional to the change in enthalpy of the reaction 12 When a material is undergoing a change in phase, it will always be accompanied by a change in: I temperature II density III entropy A B C D III only I and II only II and III I, II, and III GO ON TO THE NEXT PAGE Passage III (Questions 13–17) KAPLAN MCAT 13 Over what frequency range is the ear most sensitive? A B C D 20 to 300 Hz 300 to 2,000 Hz 2,000 to 4,000 Hz Above 4,000 Hz 17 A pitch pipe is a small pipe that is blown to produce tones used to establish the proper pitch of an instrument If a violinist plays a C note on an out of tune violin, at the same time that a pitch pipe is played, one would hear: A B C D beats resonance harmonics half tones 14 Sources A and B have a frequency of 1000 Hz If the intensity of Source A is 1000 times greater than that of Source B, what is the difference between the intensity levels of the two sources? A 30 dB B 40 dB C 1,000 dB D 10,000 dB 15 A point source emits sound waves uniformly in all directions If the radiated power is 16_ W, how close could a person get to the source before feeling pain? A 40 m B 20 m C m D m 16 A tuning fork with a frequent of 272 Hz is found to emit sound waves with a wavelength of 1.25 m What will be the wavelength of waves emitted by a different tuning fork that has a frequent of 200 Hz? A B C D 0.92 m 1.1 m 1.7 m 2.2 m GO ON TO THE NEXT PAGE as developed by Physical Sciences Questions 18 through 22 are NOT based on a descriptive passage 18 Which of the following has the smallest ionic radius? A B C D O2– F– Na+ Mg2+ 22 Which of the following is the correct description of element 37, Rb? A A heavy gray solid that may be used as a semiconductor B A silvery-white element that reacts explosively with water C A colorless gas found in air D A strong, light metal used to construct airplanes 19 Monochromatic light of a certain wavelength falls on a narrow slit On a screen a certain distance away, the distance between the second minimum and the central maximum is cm What would happen to the spacing between the two if the wavelength of the radiation were increased? A It would depend on whether the new wavelength is an odd or even multiple of the old B It would remain unchanged C It would decrease D It would increase 20 At 546 K and atm, how many liters would be occupied by 14 g of N2 gas? A B C D 11.2 L 22.4 L 33.6 L 44.8 L 21 The resistance of a circuit element can be varied by changing its length, L If the length of the resistor is doubled, the current through it: A B C D doubles remains the same is halved is quadrupled KAPLAN MCAT 25 Which of the following is/are true about Reaction 1? Passage IV (Questions 23–27) Photosynthesis is the process by which plants convert light energy to chemical energy The chemical reaction that takes place is as follows: I The reaction is not spontaneous II There is an overall decrease in entropy during the reaction III The reaction is exothermic CO2 + H2O + light → C6H12O6 + O2 Reaction where CO2 is taken in from the environment and O2 is produced and exported to the environment Sunlight travels in electromagnetic waves that are emitted in discrete packets called photons The chloroplasts in plant cells use photons of certain energy levels to split water into hydrogen and oxygen, abstracting electrons from the hydrogen atoms and incorporating them into the bonds of the sugar molecules The sugar produced by this “fixation” of CO2 is the basic carbon source, meaning food source, for the plant, and ultimately for almost all living organisms The ∆G for the reaction is +686 kcal/mol The following table gives the relevant ∆Hf values for the reactants and products in kJ/mol: CO2 H2O C6H12O6 –393.5 –285.8 –1274.5 Table A B C D I only I and II only II and III only I, II, and III 26 What is the ∆H for the reaction? A B C D +2801.3 kJ/mol –2801.3 kJ/mol +5350.3 kJ/mol –5350.3 kJ/mol 27 When light energy is absorbed, which of the following always occurs? A The energy is used to ionize the reactants B Energy is released from the bonds of the reactants C Electrons are excited to a higher energy level D Electrons return to their ground state 23 If 11 grams of H2O were consumed, how many grams of sugar would be produced? A (11 • • 180) g B (11 • • 180) g 11 C.( • • 180) g 18 11 D.( • • 180) g 18 END OF TEST 24 Which compound is oxidized in the above reaction? A B C D CO2 H2O C6H12O6 O2 GO ON TO THE NEXT PAGE as developed by Physical Sciences ANSWER KEY: B 11 A 12 C B 14 C 15 D 16 B 17 C 18 D 19 10 A 20 KAPLAN C C C A D C A D D A 21 22 23 24 25 26 27 C B C B B A C ...Physical Sciences Test Time: 35 Minutes Number of Questions: 27 MCAT PHYSICAL SCIENCES DIRECTIONS: Most of the questions in the following Physical Sciences test are organized into groups,... frequency That is, the ear is more sensitive to sounds at some frequencies than at others The faintest sound that the ear can detect at any frequency is known as the threshold of hearing This can... be produced? A (11 • • 180) g B (11 • • 180) g 11 C.( • • 180) g 18 11 D.( • • 180) g 18 END OF TEST 24 Which compound is oxidized in the above reaction? A B C D CO2 H2O C6H12O6 O2 GO ON TO THE