ACT Past Papers with Answers

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based on Ficrure I, which oiganism is essential in naintaining the L>TrLe disease bacteria in.lhe deer tick population?

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based on Table I, the avera?e peicent of households inhabited b) at least l infected person in Zones A-E of the study ar&a w'as closesi to: .4. 3010. S. According to Figure 2, the total number of new"cases of L￿rne disease was the same for both months in each of the followino pairs of mDnths EXCEPT: . D. August and iN'ovetnber. ACT-63E 39 GO ON TO THE NEXT PAGE. 40000000004 Passage 11 Qxjfluorocarbons (OFCS) are oils composed of only carbon (C), fluorine (F), and ox)'gGn (O). They are usefuL as lubricants in exposed mechanical svstetns on spacecrdft. However,. OFCS tend to decompose upon exposure to heated rneral surfaces, which usually bave a melal oxide. (MO) outer layex (see F.igure l ). Experimeni 2 The induction periods of OFCI with various pow,. dered Fc ompounds wsie measursd as in,ExperiTrcnt l al 180°C (see Table"?)..Some Df these compounds are hypolh- esized to exist. on heated Tr.et21 surfaces,. OT lo form as inor by-producis.of ihe ieaction shown in Figuie l. Table 2 OFC (liquid) + MO (solid) heal Inauclion period (sec) Cornpound Forrnula COF: (gas) + CO2 (gas) + M (solid) + liquid residue Iron(11)'oKide ITOll(IlI)fluoTide Iron(Ill)ch]oride IrorL(III)carbonate Iron(ItI)sulfate Feo FeF, F¢CL, Fe2(CO' )3 Fe-(SO,), 5,784 48 996 998 Figure I Ivhen an oil decomposes, the 3nechallical syste.Ts stop working., crippling the spacecraft. CbeTrists studied the decomposition of 2 OFCS (OFC L and OFC2). ¥Romari numerals in pareniheses indicate the amount of positive charge on'tle iron atora. ExperiFnent I In a chamber at IOO°C and O.01.atmospheres (atm) pressure, 1.5 g of OFCI ￿'aS rAixed with 50 of FO￿,_ O ), an MO. The gases produced dered iron(IlI)oxide (Fe2 3 by the dccomposition of the OFC caused the pressure to increase. The induciion period (the time'for ihe pressure to rise 10 0".20 atm) was measured. Shorter induction periods indicate more rapid decomposition. The procedure was repca&cd at different tempeyatures, and.for OFC2 (see Table l).

Paper 74 · ACT April 2006 · Form 63E · Science Test

Suppose.additional data had bten obtained Lbout the total number of infected deer tick larvae in eacb of the zones. Gik'en TabIe I, one ivould predict ihai Ihe laroest toial-of infected deer lick Ldrvae would.haii ..been found in wnich zone? H, Zone D

Paper 74 · ACT April 2006 · Form 63E · Science Test

D

Paper 74 · ACT April 2006 · Form 63E · Science Test

If, in Experiment I, a Crial had been.done ai liO°C, Ihe induction periods (in sec) for OFCI and OFC2 Thould ]nost likely have bcen whkch of the follokiing . OFCI OFC2 203 31L 311 203 301 442 442 301 Table l. Temperature Induction period (sec) OFCI OFC2 (°c) loo 120 140 160 180 200 220 1,800" 903 442 21L. 111 55 29 998 603 301 133 52 i&

Paper 74 · ACT April 2006 · Form 63E · Science Test

B ased on the results of Experiment 2, whicb compound produced the fasiesi decomposition of OFC L at 180"C ? ACT.63E 40 GO ON TO THE NEXT PAGE. 40000000004

Paper 74 · ACT April 2006 · Form 63E · Science Test

In.which of the following ways wis the design of Experiment I different from that of Experiment 2 ? In Experiment I: only OFCI was studied; in Experinent 2, only OFC2 UTaS Studied, only OFC2 was studied: in Expcriinent 2, only OFCI was studied. tcmperature varied. in Experiment 2, tempera- ture ￿'&S always the sarlle. iemperature was always the same., in EKperi- menL 2, teuLperitULe w.as varied.

Paper 74 · ACT April 2006 · Form 63E · Science Test

In Experiment I, during the decomposition of OFC2 at IOO'C, as time increas-d frotn O to 998 sec, the pres- sure in the ch￿￿be[. A, decreased from.0..20 atm to 0.01 atm.

Paper 74 · ACT April 2006 · Form 63E · Science Test

A chemist claimed that under identicaf'conditions, OFC2 will always break down in the piesence of an Mo'more quichy than will.OFCI. Are the results of Experiment I consistent with her cLaitng. period for OFCI was less than that for OFC2, period for OFCI w'as trreater than that for OFC2, period for OFCI was less than ihat foi OFC2. period for OFC l Th'as greater tharL that for OFC2,

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based on the information in Ihe passage, w'hich of the following could be Ihe chettLical formula for an OFC 7

Paper 74 · ACT April 2006 · Form 63E · Science Test

Suppose Experiment 2 were performed as described. Based Dn Student 2's hy.pothesis, the percent of ovule pollination in the felliale Zamia cones that would be CON*ered with mesh bags would be closest to. OC70. StHdent 2 Wind pollination and insect pollination each cause 50Yo of pollinatioll events in Zamia ovules. Without wind pollination, the percent of ovule pollinalioll decreases by 50Q/o. Likewise. Without insect pollination, the percent of ovule pollination decre&scs by 50%. If neither of these processes occurs, the percent of ovule pollination decreases by IOOIO.

Paper 74 · ACT April 2006 · Form 63E · Science Test

Studwnt I states that 'wind-borne pollen must be blown horizontally to enter these cones., Which of the foLLouiing describes how Student 2 responds to this statement? Student 2 argues that the shape of the: decrease the likelihood that polLen will enter these cones. increase the likelihood that pollen will. enter these cones. rnale Zamia cones creat¢s'air currents that decrease the Likelihood that pollen will enter these cones. ale Zapnia cones creates air currents thac increase. thc likclihood. that pollen will enter these cones. Wind tunnel experiments show that the shape of the femal.e Zarnia cones creates air currents that facilitatc th horizontaI rnoveroent of pollen intg these cones. Addition- ally,. male Zamia cones produce enormous quantities of pollen, a trait that is cotnmon only itl wind-pollinated .plants. AGf.63e 42 GO ON TO THE NEXT PAGE. 40000000004

Paper 74 · ACT April 2006 · Form 63E · Science Test

Suppose all experiment were performed using a naiural population of Zapnia arid that all of Ihe male cones were coN'ered ￿'1th. plastic bags that excluded insects and wind. Assutning that S tudent I's hypothesis IS cor- rect, the percent O-f Oyllle pollination would most likely be closest to: Ofo. 3310. 67Id.

Paper 74 · ACT April 2006 · Form 63E · Science Test

Student I would most likely a(rree wilh the siaternellt that Zamia pollen is: never present in Ihe male Zamia cones. not carried long distances by the wind. .S￿aller than thc pollen found in most plallts.

Paper 74 · ACT April 2006 · Form 63E · Science Test

With recrard io the experiments described in the table, Students l and 2 would most likely &ore¢ that.the pei- cent of ovule pollination would be highest Ln fertLale Zamia concs that are: not covered wilh a bag or a cyLinder. covered wich rnesh ba£TS that cxclude insects. covered Th'ith cylinders that eiclude wind, coiered with plastic baos that exclude insecis and wind.

Paper 74 · ACT April 2006 · Form 63E · Science Test

TrThich of the following would mosL-likeLy￿bc used as a control group in Experiment l ?

Paper 74 · ACT April 2006 · Form 63E · Science Test

Suppose the. 3 experiments were performed as de5ciibsd. Student 2's ELyPOthesis would be.best sup- ported if th¢ percents of ovule pollination were the same for which of the following 2 groups of female Zan7ia cones? plasiic bags and those in.Experirnent L that were not covered with plastic baus plastic.bags and Ihose iu Expcritnent 2 that weie covered with mesh bags Mesh baos and Lhose in ExperiLnent 2 thac were not covered wilh rne&h bags mcsh baos and tbose in Experimenl 3 that ￿'ere covered with cyLinders Aryf-63E 43 GO ON TO THE NEXT PAGE. 40000000004 Passage IV Three studies were conducted to investi'gate factors that'aff¢ct wind erosion. Study 3 A thifd sample of each soil..was prepared as in Study 2. EaclL tray was placed. in. sELallow .waier for . 24 hours to saturate'the sample. Each triy was then placed ' in Ehe wind,tunnel and'exposed lo arL 8.5 mlsec wind. Once the. wind had dried the top of. the soil sample sufficiently, soil particles began to appear on the white tape, At that time, the water content of the top I, rnm of the soil sampl.e was deterrrLined. This. procedure was repeated 3 roore lirnes: first adding dyed sand to the 8.5 m/sec wind, Iben using a L3 rn/sec willd, without and then with added sand. The Tesults are shown in Figure 2. Study I Samples of 3 different soils (A-C) were collecied fro]n & study area and each was analyzed for sand, silt, and clay particLe content and water conient (see Table l). Tabl&l Key Soil A Soi] B Soil C Dry particle content ((Yo) sand silt clay Water content Soil (fc) 18,1 20 no sand added ....-.. . sand added........._. Study 2 Another sample of each soil was dried LPA an oven for 24 hours, crushed, Ind passed through a screen with

Paper 74 · ACT April 2006 · Form 63E · Science Test

It was hvpothesizcd that soils with higher clay contents havc typical water contents higher than those of soils with lower clay contents. Is this hypothesis consisterLt with Ihe results of Study l ? the water content decreased. the water content also increased. water content decreased. watcr content also increased. Table 2 Oven-dried Soil Threshold wind speed (mlsec) no sand added sand added ACT.83E 44 GO ON TO THE NEXT PAGE. 40000000004 ?0. A fourth soil from'the sarne study area was analyzed using the procedures described in Scudy l and was found to colltain 73 % sand,- 15% silt, and 1210 clay particles. A water content for that soil in which ol the following ranges would be rnost consistent with the results o! Study l ?

Paper 74 · ACT April 2006 · Form 63E · Science Test

F

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based oll Study I, the water colllenr of Soil C imrnedi- ately aft¢r being saturated for the 24 hours in Study 3 was most likely.

Paper 74 · ACT April 2006 · Form 63E · Science Test

Wbich of the following st&tetfient5 about the threshold wind speeds in the trials in which no dyed sand was added to the moving air is supported by the results of Study 2 for the 3 soils? as the threshold wind speeds for ihe other 2 soils, as the IILreshoLd wind speeds for the other 2 soils. mately the same. -d on the resulrs of Study 2. for a.si!en soif, the addition of dyed satsd to the moving air.produced a threshold wind speed that was approxirnately: one-third lower'than the. threshold wind speed ',when no sand.was added to the znoving air. .the saTne"as.:Lhe thresbold'wind speed .when rio ' sand was added to Ihe. movinE air.. when no sand was added to.the moving air. sand was added to the moving air. ' 24. Suppose equal volumès of Soil A and Soil B were coL- lectcd, thoroughly rnixed, oven-dricd for 24 hours, crushed,'and' passed through,.a screen as in Study 2. If . this soil sample".were then used in. a repeat of Study 2 .using. added dyed .saud. tbe tbreshold wind speed for this s2nple would most likely be between: ' G." o.li nLlsec aud 0.20 uvsec. 45 GO ON TO THE NEXT PAGE. 40000000004 Passage V A capacitor is a device used to store electrical charge, Capczciiance is the. aLnount of charge a capacitor can hold ai a given voltage. Experiment I Two square copper plates,'each 0.05 m x 0.05 rn (surface area 2.5 x 10- m ), were separated by various thicknesses'of 'air..The.results.are showo.in Table l. Table I Plate separation . (10-, rn) A student used the circuit shown in Figure I'to per- forrn 3 experiments. (volts) 227 455 10 iesistor ammeter Plate A battery capacitor voltnlctsr Plate B Experirtient 2 Three pairs of square copper plates, each pair having a different surface ￿ea, were tested. Each pair was separated byalx 10- thickn6ss of.air. The results are sho￿'ll in Table 2. sivitch Figure I Table 2 Surface area of each.plate The parallel-plare capaciror consisted of 2 identical flat, parallel plates of copper, separated by a smaLI distance (see .Figure 2). (volts) (10-" F) IL2 opper plaies Figure 2 Experiment 3. The square copper plates fIom Experirnent I wcre separated by a L. x 10- thickness of various materials. The number K is related to each material's suitability for usc in a capacitor: The results are shown in Table 3. Initially, each plate of the capacitor was uncharged. (That is. each.pl&te contained an equal number of. positive charges and neg&tive charges.) Wherk the switch in the cir-' cult was closed, electrons (negatively charged particles) flowed frotn Plate A of the capacitor tbroush the amrneter, resistor, and battery to Plate B.. After an amouot of nega- tive charge (Q) equaling -1 x LO- coulomb flowed to P12te B, the switch was reopened, and the voLtage (V) in volts, between the charged plates was measured. Finallv, the capacitance (C) was calculated in farads (F). Table 3 Material '(voLts ) Mica Water Titaniu￿ dioxide 119 1,780 3,828 80,4 ACT4aE 46 GO ON TO THE NEXT PAGE. 40000000004

Paper 74 · ACT April 2006 · Form 63E · Science Test

A

Paper 74 · ACT April 2006 · Form 63E · Science Test

H

Paper 74 · ACT April 2006 · Form 63E · Science Test

7 kJlmole when it dissolves in water at 25°C. .Based on the data in Ficlure I, if I rjole.each of ammo- nium"nitrate and Compound A are dissolved separacely ."in equal.aTrounts of witcr.at 2),. C. bow will the.tran5- fer of heat compar= ? solucion tban WILI Compound A. . B. AmtnonjuTll.nitrate wilL absoTb in0ie.heat frotn the solution than will Compound A. solution than WILL Compound A. solution than wilL.CowpoLmd A.

Paper 74 · ACT April 2006 · Form 63E · Science Test

In ExperiLnellt 2., tbc sti]dent varied which of the fol- lowing propertiGs of th¢ cap.acitor? . J. Material con]posing tbe plates 1 27. Based on the Icsults of the 3 experiments. the capacitor with wbich of the following combinations of sep2ra- tion, surface area per plate, alld material will have the highest capacitance? Sep,aration Surface area battery capacitoi Plate B . 'switch resistor anllneter Plate A battery volttneter capacitor (m) (m,) 'l.x 10- Material Plate B iica . titanium dioxide titanium dioxide water 1% jo- 2x jo-

Paper 74 · ACT April 2006 · Form 63E · Science Test

D

Paper 74 · ACT April 2006 · Form 63E · Science Test

Assume that as K decreases. a material's Sultability foI usc bctiveen the plates of a capacitor decreases. Based on the results Df Experiment 3, which of the following correctly lists mica, Ivater, and titanjiirn dioxide in oideT of aecreasing suitability for use bctwEen the plates of. a capacitor? . .G. Mica, titanium d.ioyide,.water . Titanium dioxide, water, inica.

Paper 74 · ACT April 2006 · Form 63E · Science Test

In each trial of Experiments t-.3, afteI ihe capacitor was charged and the switch opened, what. was the charge on Plate A ? +2 x'lO- coulomb +3 x 10- coulornb switclk 2xlO- IxlO- resistor aLDmeter Plate A battery voltmeler capacitor Plate B switch Tesist-or anuneter Plate A capaciloi voltmeter Plate B switcb ACT-63E ' 47 GO ON TO THE NEXT PAGE. 40000000004 Passage Vl wh.en compounds dissolve in water, they either give off heal to, or absorb heal from, the solution. The transfer of heat (AH) is negative (Éxotkerpnic) when heat is given ofl, oi positLV¢ (endotheTmic) when heat is absorbed. Figure I shows the £lH, in kiLojollles per mole (kJlmole, where .1 mole is 6 x 10- molecules of any cornpound), when 'CoTnpounds A or B dissolve in water at 25°C. solubilily.is the maximum arnount Df a compound that"wilL dissolvc in a given volume of solvent, Figures 2 and 3 show how temperature affects the solubilily (in moleslL) of CoTnpound's A and B, respe¢iively, in ivater. ' solid +.59.8 kJlmole dissolved Compound A endothem)ic Cotnpound'A (heat absorbed from solution) dissolved Compound B H=_?0.5 kJlmole exotherllLiC (heal given off to solution) S01id Compound B Figure I 20 40 60 80 100 le￿Pe[a￿re ('C) 20 40 60 80 100 temperature (°C) Figure 2 Figure 3 ACT.63 .48 GO ON TO THE NEXT PAGE. Il.'According to Figures 2 and 3, Compounds.A and B. h&ve the .sarne solubility at what temperature, if .any.

Paper 74 · ACT April 2006 · Form 63E · Science Test

To charg.e the capacitor as described in the passage, the student caused electrons to f]ow.in.the direction(s) indicated by.which of the foLlowirig figures? resistor an]meter Plate A . voltmeter

Paper 74 · ACT April 2006 · Form 63E · Science Test

D

Paper 74 · ACT April 2006 · Form 63E · Science Test

A soluiion is made that has a concentration of I mole/L'of CortLpound A and 0.5 mole!L of Com- pound B. According to the passage, the number of molecules of Compound A in the solution is... the solution. equal to tbe number 0£ tnolecules of CoETrpound B in the solution. the solution, in the sollltioll.

Paper 74 · ACT April 2006 · Form 63E · Science Test

A" chemist claimed that compoutldg that dissolve exotbenrLically itL water decrease in solubility. as lem- perature increases. Is. her cliiTn 5upportcd by the data . in Figures 1-3 ? temperature increased. .tetnperatuie increaséd. teo]perature illcreased. D, No; tbe solubility of Compound B increLsed as temperatUTe increased.- ACT-63É 49 .GO ON TO THE NEXT PAGE. 40000000004 Passage Vll Planets revoliTe around the Sun in elliptical orbits, as shown in Figure l. Key eccentricity aphelion 40 '"semimajor aKiS = 1.5 x 10 ktn" scminajor &xis orbit 30 +-planet 25. Sun 20 perihelion 60 120 180 8 (degr¢es) 240 300 360 Fitrure I 30 .semimajor axis- 3.0 x 10 klll" 15 60 120 180 O (dsgrees) 240 300 The eccentricity.of '2n ellipse .describes its elonoation; the more eIongaled tbe el]ipse, the oreater its eccentricity. The sea]irnajor axis is haLf the lentrtb of the eLlipse. 25 senirn&jor axis = 4.5 x 10 km. ... . L5 P£rihÈlion (AngLe 8 = 0°) is the p.oint on the orbit closest to the Sun. opheliopL (0 - 180°) LS the point on the orbit farthest from the Sun. The speed of a planet varies WLth 6. The Speed of a planet versus Q is shown in Figure 2 for orbits with various eccentrlclties and sernimajor axes. 10 120 240 300 360 6 (degrees) Figure 2 GO ON TO THE NEXT PAGE. ACT.63c 50 4000000000

Paper 74 · ACT April 2006 · Form 63E · Science Test

A chetllist added either Compound'A ortompound B to water at 25'C..The temperature of the solution decreased until. the solutlQll began to £reeLé. B ased on the data in Figure. I, which compound did he Most likely add to the water7 .G. Compound A, because its is neualive. shown in the figures:

Paper 74 · ACT April 2006 · Form 63E · Science Test

B

Paper 74 · ACT April 2006 · Form 63E · Science Test

Consider a planet as il travels from 8- 0° to 0- 359° in an orbit with a seTrimajor axis of 1.5 x 10 km and n eccentiicit)r of 0.10. Bascd on the data in Figure 2, how rnany times do.es the pLanet have a Epeed of 30 kmlsec as it travels between those 2 angles? G, Two titnes H, Tb.ree times

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based on the data in Figure 2, how does Ihe speed of a planet change while it moves from perihelion to aph- elioll and while it Jnoves from aphelion to peTihelion? Perihelion to aphelion Aphelion to perihelion speed increases speed increases speed incrca5es speed. decreases speed decreases speed increases speed decreases speed decreases

Paper 74 · ACT April 2006 · Form 63E · Science Test

A planet will escape fiom the solar system if its orbital speed is greater than the escape velocity,. Based on the data in Figure 2, if ihe semirnajor axis is 1.5 x 10 kTn, i.he eccentricity is O. l O, and the escape velocity at peri- helion is 44.2 kmlsec, will the planet escape the solar system? helion is greater than the escape velocity. FLelion is less than the escape velocity. is greater than the escape iielocity, is less than tbe escape velocity.

Paper 74 · ACT April 2006 · Form 63E · Science Test

Based on the data in Figure 2, the orbital speed of a planet will most likel! remain constant if the ccccn- tricity of Ihe planet's orbit is.. exactly O. exactly I,

Paper 74 · ACT April 2006 · Form 63E · Science Test

B ased on the data in FiguIe 2, for a planet in all orbit around the Sun with a sett]imajoL axis. of 3.0 x 1.0 L and an eccentFlClty of 0.05, the speed at 9- 0° will be: greater than 28 kmlsec. END OF TEST4 STOPI DO NOT RETURN TO ANY OTHER TEST. ACT-63E 51 FoATh ts3E (April 2006) Atllalia Hernandez's Ballet FollJorico de Mexico Math Readin Science i) c