Science. Science. Passage I

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1 Passage I 1. D Category: Figure Interpretation Strategic Advice: Pay attention to all of the conditions in the question stem finding the answer to this question depends on locating the right line in the table. Getting to the Answer: There are two rows in the table that refer to Lagerstroemia Natchez grown at a latitude of 28 degrees. (Make sure to ignore the row containing Lagerstroemia Natchez grown at a latitude of 33 degrees!) Reading across the two rows, you can see that the plants have heights of 8.6 and 7.6 meters. Only D encompasses this range. 2. G Category: Figure Interpretation Strategic Advice: Grab low difficulty points like these by making sure you re looking at the right figure. Getting to the Answer: Flowering growth is on the y-axis of Figure 1, so start by looking at that figure. The slope of the line indicates the rate of flowering growth, so you should look for the segment that has the steepest positive slope. According to the figure, flowering growth increases only slightly in the Juvenile and Adult phases, and it decreases during the Death phase. The only phase containing a large increase in flowering growth, indicated by a steep upward slope, is the Intermediate phase, G. 3. B Category: Figure Interpretation Strategic Advice: Don t rely on memory alone here copy a few numbers or circle rows on the table so you don t get your data mixed up. Getting to the Answer: This question merely requires you to read the table accurately. The four species mentioned in the answer choices grew to heights of 2.4, 6.4, 4.6, and 4.9 meters, respectively. Of these four numbers, 6.4 is clearly the greatest, so B is correct F Category: Figure Interpretation Strategic Advice: Don t overthink problems that require only a little bit of interpretation; the data in the table will probably take you closer to the answer than you think. Getting to the Answer: Take a look at the table and summarize what you know about each plant variety. Lagerstroemia indica Catawba reached a height of 2.7 meters in soil and compost, and Lagerstroemia fauriei Kiowa was 8.3 meters tall in soil and compost. Lagerstroemia Chickasaw and Lagerstroemia Natchez were not grown in compost, so eliminate G and J.

2 Lagerstroemia indica Catawba comes closest to a height of 3 meters, so F is the correct answer. 5. D Category: Patterns Strategic Advice: This sort of question should not involve overly complex reasoning you re simply looking for the answer choice that describes, in words, the data in the figure. Getting to the Answer: Simply compare the statement in each choice to the information in the figure only one choice should agree closely with the data. A cannot be correct, since the rate of increase for flowering growth changes in each phase. B and C don t match the data either the graph during the Juvenile phase is mostly flat with just a small increase towards the end. D is correct. Figure 1 depicts little increase in flowering growth until the onset of the Intermediate phase. 51 Passage II 6. G Category: Scientific Reasoning Strategic Advice: Always remember, careful reading is just as important as good reasoning skills, especially on easier questions. Getting to the Answer: This question simply requires you to read every answer choice and compare it to the data presented. F contradicts the passage in both experiments, sampling was done on a daily basis. H is tempting, but it switches the experiment numbers, making the statement untrue. J does not work either both pollutants mentioned were sampled in each experiment. Only G agrees with the experimental procedure as described. 7. B Category: Scientific Reasoning Strategic Advice: Questions that ask about which experiment to perform next should always build on the data in the passage. Getting to the Answer: Although several of these procedures might be worthwhile, only one answers the question that is raised. A is incorrect because temperature was not one of the variables mentioned in the question stem, so there is no reason to study it. C and D mention procedures that would not provide any information about respiratory ailments, so these cannot be correct. Only B correctly proposes studying all three variables mentioned in the question (carbon monoxide, sulfur dioxide, and respiratory ailments) and builds on the data in the passage. 8. J Category: Scientific Reasoning

3 Strategic Advice: When a question asks you about testing hypotheses, make sure your answer choice always addresses the exact research question it mentions. Getting to the Answer: To test this hypothesis, you ll need an experiment that relates sulfur dioxide and the acidity of lakes. F doesn t provide a link between sulfur dioxide and lake acidity, so this can t be correct. G might be tempting because the passage does mention respiratory ailments, but fails to provide a direct link between sulfur emissions and lake acidity. Eliminate it. H is also incorrect. While the amount of coal burned might influence the amount of sulfur dioxide, increasing it won t tell you anything about the link between sulfur dioxide and the acidity of the lake. Only J connects sulfur dioxide to the acidity of lake water. 9. A Category: Scientific Reasoning Strategic Advice: Don t forget about the introductory paragraph before the experiments it contains valuable background information. Getting to the Answer: The first paragraph says, Scientists noted an increase in acid rainfall and reports of respiratory ailments in a certain community. They suspected that both of these outcomes were due to increased levels of airborne pollutants, such as carbon monoxide and sulfur dioxide, entering the atmosphere in that community. Since Experiment 1 involved measuring the levels of these pollutants near two highways, it is reasonable to conclude that the scientists were trying to determine if pollution from traffic was the source of these respiratory problems. This fits well with the hypothesis expressed in A. B is incorrect. The power plant is only a factor in Experiment 2, not Experiment 1. C incorrectly states that Experiment 1 was concerned with measuring rainfall. Though D does incorporate the ideas of traffic and pollution, it has nothing to do with the respiratory problems mentioned in the question stem. 10. F Category: Scientific Reasoning Strategic Advice: Words such as EXCEPT are printed in caps for a reason so you can t miss them. Make sure you don t get sidetracked and forget the question. Getting to the Answer: The experiments in this passage indicate that emissions from highway traffic and from power plants contribute to increases in airborne pollutants. Thus, F would increase rather than reduce highway traffic and subsequent pollution, making it the best answer. G contradicts the data in the passage. Highway traffic is indicated as a source of pollutants, so traffic limits would help reduce pollution due to highway vehicles. H also contradicts the passage. Coal-burning is the source of the power plant s pollutant emissions, so reducing coal-burning would reduce emission levels. J contradicts the passage as well. Filters would not allow sulfur dioxide to reach the outside air, thus reducing nearby levels of this airborne pollutant D Category: Patterns Strategic Advice: Consider the information you re given in the question stem. If

4 emissions become less concentrated further away from their sources, what would you expect to happen if you moved closer to the source? Getting to the Answer: If emissions farther from a source are less concentrated, then you can expect emissions measured closer to a source (the roadway, in this case) to be more concentrated. Thus, the correct answer will be larger than the data point for Highway 1 on January 7 in the table, which is 3.2 parts per million. A, B, and C are all smaller than this figure, leaving D as the correct response. 53 Passage III 12. H Category: Scientific Reasoning Strategic Advice: In passages with multiple experiments, it s even more important to circle the methods during Step 1 of the Kaplan Method for so that you don t get mixed up from one experiment to the next. Getting to the Answer: The table and description for Experiment 3 both indicate that the experiment studied how levels of UV-B light varied by the time of day they were measured. H is the only choice that correctly indicates the changing variable; the other choices refer to quantities that are not manipulated in Experiment B Category: Patterns Strategic Advice: Focus on the variables that affect only UV-A light don t get distracted by any others. Getting to the Answer: You first need to figure out which factors lead to higher and lower levels of UV-A light to answer this question. From Experiment 1, you can see that UV-A levels are higher in summer and at higher elevations, and from Experiment 2, you can see that time of day also makes a difference. Experiment 3 does not deal with UV-A light. A and D both deal with UV-B light. Since the relationship between UV-A and UV-B light is never discussed, you can t assume that reducing one will reduce the other. Eliminate these. B is consistent with the passage. Shorter summers and longer winters should result in fewer days of high UV-A levels. Keep this one. C is the opposite of B and would likely increase exposure to UV-A light. B, then, is correct. 14. G Category: Patterns Strategic Advice: If a question asks how one variable affects another, there is bound to be an experiment that addresses that relationship you just have to find it. Getting to the Answer: Essentially, this question is asking how UV-B levels are different when the sun is overhead, in the middle of the day, and when it is low on the horizon, later in the day. Experiments 2 and 3 both discuss the relationship between time of day and UV-B levels, though it is probably easier to see this relationship in Experiment 3. According to the table, UV-B levels decrease every hour after the sun is directly overhead, so you should predict that UV-B levels will be lower when the sun is low on the horizon, which corresponds to G.

5 15. C Category: Patterns Strategic Advice: Questions that introduce a new variable that behaves just like the other variables in the experiment are really just complicated ways of asking you to identify the patterns in the data. Getting to the Answer: This question is too open-ended to make a prediction, so go directly to the answer choices. The issue of how UV levels change from year to year is never mentioned in the passage, so rule out A and B. That leaves C and D, which ask about UV levels when the sun is directly overhead. Experiments 2 and 3 indicate that both UV-A and UV-B levels are higher when the sun is overhead, so if UV-C behaves similarly, as assumed in the question stem, C must be correct. 16. J Category: Patterns Strategic Advice: If one question repeats concepts or relationships used in previous questions, you re in luck you have a chance to get some quick, easy points and double-check your earlier work at the same time. Getting to the Answer: This question also asks about the relationship between UV levels and time of day, but in a slightly different manner don t let the altered phrasing throw you off. You ve previously found that both UV-A and UV-B are higher when the sun is overhead and lower at later times of day, so that means both levels decrease as the number of hours after the sun is overhead increases. J is the only choice that captures this relationship accurately. 17. D Category: Patterns Strategic Advice: If you re not sure which table to examine, you might get some help from the answer choices check and see if the numbers in them are unique to one particular table or experiment. Getting to the Answer: This question looks complicated, but the mention of UV-A levels, the summer, and measuring 30 minutes after the sun is overhead all point to the design of Experiment 1, particularly the information in the second half of Table 1. Since the elevation mentioned in the question stem is higher than all of those in the table, and because UV-A levels increase with greater elevation, predict that the levels of UV-A in this community will be higher than all of the values in the Summer section of Table 1. Only D matches this prediction. Passage IV G Category: Patterns Strategic Advice: When presented with multiple tables, always make sure you re reading the right one you don t want to miss a straightforward question because you read the wrong table.

6 Getting to the Answer: As you look down the information presented in Table 1, the number in the Precession rate column increases. So does the corresponding value of r, representing the distance from the surface to the gyroscope s center of gravity. Thus you can conclude that precession rate increases as r increases, which matches G. F and H contract this data. You should immediately have eliminated J because mass is not addressed in Experiment C Category: Patterns Strategic Advice: You don t have to figure out the exact shape of the graph just enough to distinguish it from the incorrect answer choices. Getting to the Answer: Experiment 2 shows a steady decrease in precession rate as spin rate increases, with no sign of this trend reversing indicated in the table. This best corresponds to C, which also shows the precession rate (y-axis) decreasing as the spin rate (x-axis) increases. A shows an initial increase in precession rate before it decreases, which is not supported by the data in the table. B shows the opposite trend precession rate increasing as spin rate increases. D shows an initial decrease in precession rate, but the subsequent increase is not supported by the table. 20. F Category: Scientific Reasoning Strategic Advice: In any scientific method question, make sure you have a firm understanding of the hypothesis before going any further. Getting to the Answer: To test a hypothesis about precession rate and gravity, the scientist would have to measure the precession rate at several different gravities. The question tells you that gravity decreases as distance from the Earth increases. One way to test this hypothesis would be to measure gyroscopes at different distances from Earth, which matches F. G would not provide any new data about gravity, as the conditions are the same as in Experiment 3. H is incorrect because nothing in the passage or question stem indicates that orbit direction has anything to do with gravity. J would tell you something about changing precession rates with spin rate (as in Experiment 2), but it has little to do with gravity. 21. C Category: Patterns Strategic Advice: Save difficult questions like this one for last, but don t guess without even trying to find your way to the answer. Getting to the Answer: Start this question by looking back at Tables 1 and 2. Table 1 relates r and precession rate, and Table 2 relates spin rate and precession rate. You re told in the question stem that r in Experiment 2 is 6 cm. r only appears in Table 1, and Table 1 shows the precession rate for an r of 6 cm is 14 rpm. Now you know r and the precession rate. However, the question is asking you to find the spin rate in Experiment

7 1. To find that, look at Table 2 (you can move back and forth because, according to the question, r equals 6 in Experiment 2). The spin rate for a gyroscope with an r of 6 and a precession rate of 14 rpm is 750 rpm. So, you can assume that 750 rpm was the spin rate used throughout Experiment G Category: Scientific Reasoning Strategic Advice: When you have multiple experiments to keep track of, make sure you always know exactly what effect or variable was tested in each one. Getting to the Answer: The main effect tested in Experiment 1 was the effect of the gyroscope s size on its precession rate, specifically the distance from the spinning surface to the gyroscope s center of mass. If it had not been known that size affects precession rate, the scientist might not have been as careful to use the same size gyroscope throughout Experiment 2, which matches G. F is unlikely, as gyroscope mass was not addressed in either experiment. H can t be correct. Although surface type could influence precession, that was not the factor tested in Experiment 1. J was a factor not explicitly tested in Experiment B Category: Scientific Reasoning Strategic Advice: Always remember any good experiment should involve manipulating the variable being tested while keeping all other quantities constant. Getting to the Answer: To investigate the effects of gyroscope mass, one needs a way to vary mass without changing any other properties of the gyroscope. One way to do this is by using different materials, as suggested in B. A is too vague to be correct. Although gyroscopes from different companies could potentially have different masses, they might also have different shapes or sizes. Mass is the only variable you want to manipulate in this investigation. C doesn t address mass, so it s not a good answer. There is no need to test different gravities when the main variable in question can be manipulated right on Earth. D is the reverse of what you want it tests the effects of gyroscope size, which is already investigated in Experiment 1. Passage V H Category: Scientific Reasoning Strategic Advice: In questions like this, the correct answer will be one that conflicts with both theories, rather than simply being irrelevant to one theory or another. Getting to the Answer: The two theories differ widely, but they both broadly involve water droplets in clouds coming together in some way until they fall to the ground. Examine the answer choices one by one to find a situation that violates both viewpoints. F agrees with the first theory, so this can t be a situation with which supporters of both viewpoints would disagree. G agrees with the second theory, so this is incorrect.

8 H looks like a good option, since both theories rely on water droplets to produce precipitation. J agrees with both theories, so it s also incorrect B Category: Scientific Reasoning Strategic Advice: In questions like this one, you can easily rule out answer choices that are irrelevant to one theory or both. Getting to the Answer: The two theories differ with regard to the mechanism of how precipitation forms in clouds, but the net result precipitation appears to be the same. A cannot be correct. The shape of the cloud formation is not mentioned in either theory, so they cannot differ on this point. B looks good. The first theory has liquid drops forming in the cloud while the second refers to ice crystals. C cannot be correct. Neither theory makes predictions about the amount of precipitation, so they cannot differ on this point. D cannot be correct either. Neither theory makes any mention of climate, so they cannot differ on this point. 26. F Category: Scientific Reasoning Strategic Advice: When you see two answer choices that are exact opposites of each other, it s often a good bet that one of them will be correct. Getting to the Answer: This theory essentially relies on droplets colliding and sticking together until the drops are large enough to form precipitation. Anything that increases the likelihood of these events occurring, then, should increase the likelihood of rainfall. F looks like a good choice, as a high rate of collisions would mean more collisions, which in turn would mean more coalescence and more raindrops. Keep this one. G is too vague to be correct. A variable rate could mean fewer collisions, and therefore less coalescence and fewer raindrops, reducing the likelihood of producing rain. H is incorrect, as the theory does not rely on temperature. J is irrelevant, as nothing in the theory mentions time since the last rainfall. 27. B Category: Scientific Reasoning Strategic Advice: Even if they are not emphasized, pay close attention to words in the question stem that indicate both theories, one theory, or neither theory. Getting to the Answer: Both theories state that heavy particles end up falling to the ground as precipitation. So, a likely conclusion of both would be that the heavy particles found by the weather balloon will be turning into precipitation soon. B is the best match for this prediction. A is incorrect because the idea of impurities in the air is relevant only to the second theory. C is incorrect because the idea of particles colliding is only relevant to the first theory. D is incorrect because the idea of clouds changing altitude is not addressed in either theory.

9 28. H Category: Scientific Reasoning Strategic Advice: Remember, you should answer this question after reading the Ice Crystal Theory, but before you answer questions addressing both theories. Getting to the Answer: The major point of the Ice Crystal Theory is that impurities in the air lead to precipitation, so look for an answer choice that addresses impurities. Only H mentions impurities, and it is the correct answer. F cannot be correct, as thunder and lightning are not mentioned in the Ice Crystal Theory. G cannot be correct, as the Ice Crystal Theory never mentions atmospheric density. J is the opposite of the correct answer; fewer impurities would mean less precipitation according to the Ice Crystal Theory. 29. C Category: Scientific Reasoning Strategic Advice: You should answer this question before you read the Ice Crystal Theory. Getting to the Answer: The main point of the Collision and Coalescence Theory is that precipitation is formed when small droplets collide in clouds, resulting in bigger droplets that are too heavy to remain suspended in the cloud. You can predict that the correct choice will have to do with the collision and coalescence of water droplets. A does not support the idea that smaller droplets collide and combine to form bigger droplets, which is the crux of the Collision and Coalescence Theory. B can t be right, as the theory never mentions crystallization. C corresponds fairly well to Step II of the Collision and Coalescence Theory. D, like B, is not mentioned in the theory. (Both answer choices are drawn from the Ice Crystal Theory, and might be tempting if you had answered this question after reading that theory.) 30. H Category: Scientific Reasoning Strategic Advice: Don t try to answer questions based on your own world knowledge stick to figuring out whether choices agree or disagree with the theory presented. Getting to the Answer: The theory states that precipitation forms in a cloud as ice crystals and often melts as it falls to produce rain. However, as this is the Ice Crystal Theory, any possibility that does not begin with precipitation in the clouds in ice form will not contradict the theory. F is incorrect, as the passage says it is possible. G is not directly stated to be possible, but it does not contradict anything in the theory. H begins with water in the clouds rather than ice, making it incompatible with the Ice Crystal Theory. This looks good. J, like G, is not directly mentioned, but is not ruled out by the theory. 58

10 Passage VI 31. C Category: Patterns Strategic Advice: Detecting patterns is more difficult when three variables are involved. To simplify this question, work methodically through one variable at a time. Getting to the Answer: The question asks you to identify the trend between e and r for any value of n. If you look back at the table, you ll see that n can be either 2, 3, or 4. Start by looking at the n = 2 data. As the values of e increase from 4 to 7, the values of r decrease steadily from 9.1 to 5.7. Next, look at the n = 3 data the same holds true, as it does for the n = 4 data. C, then, is the correct answer. 32. F Category: Patterns Strategic Advice: Use the trends in the data to make a prediction for the correct answer. Getting to the Answer: You saw in question 31 that for a given value of n, higher values of e give lower values of r, and vice versa. For n = 2, the lowest value of e given is 4, with a corresponding r = 9.1. If the trend continues as expected, you can predict a lower e will have an r value that is higher than 9.1. The only answer choice given that is larger than 9.1 is F C Category: Scientific Reasoning Strategic Advice: Don t try thinking back to chemistry class as the question states, all the information you need is right in the passage. Getting to the Answer: Start this question by asking yourself how you might decrease an atom s negative charge that is, how you might make it less negative. Check to see where negative charge is mentioned in the passage. The opening paragraph states that electrons are an atom s negatively charged particles. You can expect, then, that removing electrons will decrease an atom s negative charge. Removing electrons isn t one of the answer choices, so you ll have to think further about which answer choice might result in the removal of an electron, thus decreasing the atom s charge. A is incorrect. According to Table 1, decreasing the radius (r) corresponds to an increased number of electrons in the outer shell (e), which would only increase the atom s negative charge. Eliminate this. B is incorrect, as nothing in the passage suggests a link between chemical bonds and electron loss. C looks good. After Figure 1, the passage says that I is the energy required to remove an electron, so you can infer that the application of energy causes the electron to be removed. Keep this. D is incorrect. The passage doesn t tell you how the number of shells and the total number of electrons in an atom are related. 34. J Category: Patterns

11 Strategic Advice: If the question stem and answer choices group the data in particular ways, examine the table in the same groupings. Getting to the Answer: This question asks you to examine the trend between the number of electrons in an atom s outer shell (e) and c according to each value of n. Just like with question 31, look at e and c for each value of n separately. For n = 2, c increases as e increases. Cross off H, as this doesn t contain n = 2. For n = 3, c again increases as e increases. Cross off F, because it doesn t contain n = 3. For n = 4, again, c increases as e increases. The correct answer must be J. 35. D Category: Figure Interpretation Strategic Advice: If a question does not use the same symbols as the table to refer to variables, make sure to go back and check what each symbol represents. Getting to the Answer: Since the question asks about removing electrons from shells, look for the row in the table with the greatest value of I (which, according to the passage, is the energy required to remove one electron from the atom s outer shell. ) Each element mentioned only has one entry in the table, so its value of I should be easy to find. The I values for Si, Cl, C, and F are 8.2, 13.0, 11.2, and 17.4, respectively. Of these, 17.4, the value for F, is greatest, so the answer is D. Passage VII 36. J Category: Figure Interpretation Strategic Advice: This question asks you to confirm a theory by looking at a pair of trials in which the initial values of [H 2 ] and [F 2 ] are switched. You can avoid nearly all of the actual work involved in this by first checking the answer choices for a pair of trials that actually switch the initial values of [H 2 ] and [F 2 ]. Getting to the Answer: Start with F. Trials 1 and 2 both use the same initial values of [H 2 ] and [F 2 ], so that doesn t tell you anything about what switching the initial values does. Eliminate F. G has the same problem the initial concentrations of both chemicals for Trials 7 and 8 are the same. Don t spend any more time thinking about G eliminate it. H has different values for the two trials, but the concentrations are not switched. Trial 8 uses 1 mol/l for [H 2 ] and [F 2 ], and Trial 11 uses 0.75 and 0.25 mol/l, respectively. Only J refers to two trials in which the initial concentrations of the two chemicals (0.5 and 1.0 mol/l) are exactly reversed from one trial to the other D Category: Patterns Strategic Advice: Remember the cardinal rule of experimentation when examining the effect of a certain variable or variables, keep all other quantities equal between trials. Getting to the Answer: You need to start by finding a pair of trials where the initial concentrations for both H 2 and F 2 are doubled from trial to trial, but everything else is the same. Trials 4 and 8 work well for this purpose. The final value for [HF] in Trial 4 is

12 0.778; when the initial quantities are doubled in Trial 8, the final value for [HF] is 1.557, which is almost exactly twice its final value from Trial 4. Thus, D is the correct answer. 38. G Category: Patterns Strategic Advice: There are a lot of variables to keep track of in a problem like this, so make sure to choose your comparison trials very carefully. Getting to the Answer: You can immediately rule out F and H, since the question stem states that the initial concentrations will be kept constant. However, to see if temperature affects final concentration values, you will still need to find at least two trials where the temperature changes, but all other initial values are kept the same. This is true for all of Trials 1 6. As you can see, the temperature is steadily increased from Trial 1 to Trial 6, and this causes a steady decrease in the final concentration of HF, making G the correct answer A Category: Patterns Strategic Advice: First, find comparison trials in which only K eq and temperature are changing. Then, focus only on those two variables. Circle the columns for K eq and temperature to make sure you don t accidentally look at the wrong column. Getting to the Answer: As with the previous question, any or all of Trials 1 6 provide good examples of trials where temperature is the only initial variable being manipulated. If you just trace down the columns, you will see that as temperature is increased, the value of K eq becomes lower and lower. Thus, the correct answer is A. 40. J Category: Patterns Strategic Advice: Since there is no data in the table for reactions conducted with 2 mol/l initial concentrations of H 2 and F 2, you know you re going to have to identify the trends in the data and predict an answer based on them. Getting to the Answer: You ve already seen that doubling the initial concentrations of H 2 and F 2 results in a doubled final concentration of HF. If you don t remember this, you ll need to find a pair of trials, such as Trials 3 and 7, that show that doubling the initial concentrations of H 2 and F 2 doubles the final concentration of HF. Then, you should find a trial conducted at 700 K. Trial 8 is the easiest one to work with, because the initial concentrations of H 2 and F 2 are each 1 mol/l and. Doubling them would give you concentrations of 2 mol/l. The final concentration of HF in Trial 8 is mol/l; you need not perform the calculation exactly to see that once doubled, the result will come closest to 3.2 mol/l, or J.