chemistry

CLEP TIG - Chemistry XPP 79991-007739 Dr01 7/30/09 ta Revs 8/2/09 ta Rev 8/6/09 ta Dr02 8/20/09 ta Revs 8/25/09 ta Preflight 9/15/09 ta New Job 96659-007739 Dr01 11/13/12 ta Revs Dr0111/14/12 ta Dr02 11/28/12 ta

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Test InformationGuide:College-LevelExaminationProgram

2012-13

Chemistry

2012 The College Board. All rights reserved. College Board, College-Level ExaminationProgram, CLEP, and the acorn logo are registered trademarks of the College Board.


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CLEP TEST INFORMATIONGUIDE FOR CHEMISTRY

History of CLEP

Since 1967, the College-Level Examination Program(CLEP) has provided over six million people withthe opportunity to reach their educational goals.CLEP participants have received college credit forknowledge and expertise they have gained throughprior course work, independent study or work andlife experience.

Over the years, the CLEP examinations have evolvedto keep pace with changing curricula and pedagogy.Typically, the examinations represent material taughtin introductory college-level courses from all areasof the college curriculum. Students may choose from33 different subject areas in which to demonstratetheir mastery of college-level material.

Today, more than 2,900 colleges and universitiesrecognize and grant credit for CLEP.

Philosophy of CLEP

Promoting access to higher education is CLEPsfoundation. CLEP offers students an opportunity todemonstrate and receive validation of theircollege-level skills and knowledge. Students whoachieve an appropriate score on a CLEP exam canenrich their college experience with higher-levelcourses in their major field of study, expand theirhorizons by taking a wider array of electives andavoid repetition of material that they already know.

CLEP Participants

CLEPs test-taking population includes people of allages and walks of life. Traditional 18- to 22-year-oldstudents, adults just entering or returning to school,home-schoolers and international students who needto quantify their knowledge have all been assisted byCLEP in earning their college degrees. Currently,58 percent of CLEPs test-takers are women and51 percent are 23 years of age or older.

For over 30 years, the College Board has worked toprovide government-funded credit-by-examopportunities to the military through CLEP. Militaryservice members are fully funded for their CLEP examfees. Exams are administered at military installationsworldwide through computer-based testing programs

and also in forward-deployed areas throughpaper-based testing. Approximately one-third of allCLEP candidates are military service members.

2011-12 National CLEP Candidates by Age*

These data are based on 100% of CLEP test-takers who responded to this survey question during their examinations.

*

Under 1810%

18-22 years39%

23-29 years22%

30 years and older29%

2011-12 National CLEP Candidates by Gender

42%

58%

Computer-Based CLEP Testing

The computer-based format of CLEP exams allowsfor a number of key features. These include:

a variety of question formats that ensure effectiveassessment

real-time score reporting that gives students andcolleges the ability to make immediate credit-granting decisions (except College Composition,which requires faculty scoring of essays twice amonth)

a uniform recommended credit-granting score of50 for all exams

rights-only scoring, which awards one point percorrect answer

pretest questions that are not scored but providecurrent candidate population data and allow forrapid expansion of question pools


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CLEP Exam Development

Content development for each of the CLEP examsis directed by a test development committee. Eachcommittee is composed of faculty from a widevariety of institutions who are currently teachingthe relevant college undergraduate courses. Thecommittee members establish the test specificationsbased on feedback from a national curriculumsurvey; recommend credit-granting scores andstandards; develop and select test questions; reviewstatistical data and prepare descriptive material foruse by faculty (Test Information Guides) and studentsplanning to take the tests (CLEP Official Study Guide).

College faculty also participate in CLEP in otherways: they convene periodically as part ofstandard-setting panels to determine therecommended level of student competency for thegranting of college credit; they are called upon towrite exam questions and to review forms and theyhelp to ensure the continuing relevance of the CLEPexaminations through the curriculum surveys.

The Curriculum Survey

The first step in the construction of a CLEP exam isa curriculum survey. Its main purpose is to obtaininformation needed to develop test-contentspecifications that reflect the current collegecurriculum and to recognize anticipated changes inthe field. The surveys of college faculty areconducted in each subject every three to five yearsdepending on the discipline. Specifically, the surveygathers information on:

the major content and skill areas covered in theequivalent course and the proportion of the coursedevoted to each area

specific topics taught and the emphasis given toeach topic

specific skills students are expected to acquire andthe relative emphasis given to them

recent and anticipated changes in course content,skills and topics

the primary textbooks and supplementary learningresources used

titles and lengths of college courses thatcorrespond to the CLEP exam

The Committee

The College Board appoints standing committees ofcollege faculty for each test title in the CLEP battery.Committee members usually serve a term of up tofour years. Each committee works with contentspecialists at Educational Testing Service to establishtest specifications and develop the tests. Listedbelow are the current committee members and theirinstitutional affiliations.

Donnie Byers,Chair

Johnson County CommunityCollege

Michael Abraham University of Oklahoma

Abdul Mohammed North Carolina CentralUniversity

The primary objective of the committee is toproduce tests with good content validity. CLEPtests must be rigorous and relevant to the disciplineand the appropriate courses. While the consensus ofthe committee members is that this test has highcontent validity for a typical Chemistry course orcurriculum, the validity of the content for a specificcourse or curriculum is best determined locallythrough careful review and comparison of testcontent, with instructional content covered in aparticular course or curriculum.

The Committee Meeting

The exam is developed from a pool of questionswritten by committee members and outside questionwriters. All questions that will be scored on a CLEPexam have been pretested; those that pass a rigorousstatistical analysis for content relevance, difficulty,fairness and correlation with assessment criteria areadded to the pool. These questions are compiled bytest development specialists according to the testspecifications, and are presented to all the committeemembers for a final review. Before convening at atwo- or three-day committee meeting, the membershave a chance to review the test specifications andthe pool of questions available for possible inclusionin the exam.


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At the meeting, the committee determines whetherthe questions are appropriate for the test and, if not,whether they need to be reworked and pretestedagain to ensure that they are accurate andunambiguous. Finally, draft forms of the exam arereviewed to ensure comparable levels of difficulty andcontent specifications on the various test forms. Thecommittee is also responsible for writing anddeveloping pretest questions. These questions areadministered to candidates who take the examinationand provide valuable statistical feedback on studentperformance under operational conditions.

Once the questions are developed and pretested,tests are assembled in one of two ways. In somecases, test forms are assembled in their entirety.These forms are of comparable difficulty and aretherefore interchangeable. More commonly,questions are assembled into smaller,content-specific units called testlets, which can thenbe combined in different ways to create multiple testforms. This method allows many different forms tobe assembled from a pool of questions.

Test Specifications

Test content specifications are determined primarilythrough the curriculum survey, the expertise of thecommittee and test development specialists, therecommendations of appropriate councils andconferences, textbook reviews and other appropriatesources of information. Content specifications takeinto account:

the purpose of the test

the intended test-taker population

the titles and descriptions of courses the test isdesigned to reflect

the specific subject matter and abilities to be tested

the length of the test, types of questions andinstructions to be used

Recommendation of the AmericanCouncil on Education (ACE)

The American Council on Educations CollegeCredit Recommendation Service (ACE CREDIT)has evaluated CLEP processes and procedures for

developing, administering and scoring the exams.Effective July 2001, ACE recommended a uniformcredit-granting score of 50 across all subjects, withthe exception of four-semester language exams,which represents the performance of students whoearn a grade of C in the corresponding collegecourse.

TheAmerican Council on Education, the majorcoordinating body for all the nations higher educationinstitutions, seeks to provide leadership and a unifyingvoice on key higher education issues and to influencepublic policy through advocacy, research and programinitiatives. For more information, visit theACECREDIT website at www.acenet.edu/acecredit.

CLEP Credit Granting

CLEP uses a common recommended credit-grantingscore of 50 for all CLEP exams.

This common credit-granting score does not mean,however, that the standards for all CLEP exams arethe same. When a new or revised version of a test isintroduced, the program conducts a standard settingto determine the recommended credit-granting score(cut score).

A standard-setting panel, consisting of 1520 facultymembers from colleges and universities across thecountry who are currently teaching the course, isappointed to give its expert judgment on the level ofstudent performance that would be necessary toreceive college credit in the course. The panelreviews the test and test specifications and definesthe capabilities of the typical A student, as well asthose of the typical B, C and D students.* Expectedindividual student performance is rated by eachpanelist on each question. The combined average ofthe ratings is used to determine a recommendednumber of examination questions that must beanswered correctly to mirror classroom performanceof typical B and C students in the related course. Thepanels findings are given to members of the testdevelopment committee who, with the help ofEducational Testing Service and College Boardpsychometric specialists, make a final determinationon which raw scores are equivalent to B and C levelsof performance.

*Student performance for the language exams (French, German and Spanish)is defined only at the B and C levels.


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Chemistry

Description of the Examination

The Chemistry examination covers material thatis usually taught in a one-year college coursein general chemistry. Understanding of thestructure and states of matter, reaction types,equations and stoichiometry, equilibrium, kinetics,thermodynamics, and descriptive and experimentalchemistry is required, as is the ability to interpretand apply this material to new and unfamiliarproblems. During this examination, an onlinescientific calculator function and a periodic tableare available as part of the testing software.

The examination contains approximately75 questions to be answered in 90 minutes.Some of these are pretest questions that willnot be scored. Any time spent on tutorials andproviding personal information is in addition tothe actual testing time.

Knowledge and Skills Required

Questions on the Chemistry examination requirecandidates to demonstrate one or more of thefollowing abilities.

Recall remember specific facts; demonstratestraightforward knowledge of information andfamiliarity with terminology

Application understand concepts andreformulate information into other equivalentterms; apply knowledge to unfamiliar and/orpractical situations; use mathematics to solvechemistry problems

Interpretation infer and deduce from dataavailable and integrate information to formconclusions; recognize unstated assumptions

The subject matter of the Chemistry examination isdrawn from the following topics. The percentagesnext to the main topics indicate the approximatepercentage of exam questions on that topic.

20% Structure of MatterAtomic theory and atomic structure Evidence for the atomic theory Atomic masses; determination bychemical and physical means

Atomic number and mass number;isotopes and mass spectroscopy

Electron energy levels: atomic spectra,quantum numbers, atomic orbitals

Periodic relationships, including,for example, atomic radii, ionizationenergies, electron affinities,oxidation states

Chemical bonding Binding forces Types: covalent, ionic, metallic,macromolecular (or network),dispersion, hydrogen bonding

Relationships to structure andto properties

Polarity of bonds, electronegativities Geometry of molecules, ions andcoordination complexes: structuralisomerism, dipole moments ofmolecules, relation of propertiesto structure

Molecular models Valence bond theory; hybridization oforbitals, resonance, sigma and pibonds

Other models; for example, molecularorbital

Nuclear chemistry: nuclear equations,half-lives, and radioactivity; chemicalapplications

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19% States of MatterGases Laws of ideal gases; equations of statefor an ideal gas

Kinetic-molecular theory Interpretation of ideal gas laws on thebasis of this theory

The mole concept; Avogadros number

Dependence of kinetic energy ofmolecules on temperature:Boltzmann distribution

Deviations from ideal gas lawsLiquids and solids Liquids and solids from the kinetic-molecular viewpoint

Phase diagrams of one-componentsystems

Changes of state, critical phenomena Crystal structureSolutions Types of solutions and factors affectingsolubility

Methods of expressing concentration Colligative properties; for example,Raoults law

Effect of interionic attraction oncolligative properties and solubility

12% Reaction TypesFormation and cleavage of covalent bonds Acid-base reactions; concepts ofArrhenius, Brnsted-Lowry and Lewis;amphoterism

Reactions involving coordinationcomplexes

Precipitation reactionsOxidation-reduction reactions Oxidation number The role of the electron inoxidation-reduction

Electrochemistry; electrolytic cells,standard half-cell potentials, predictionof the direction of redox reactions, effectof concentration changes

10% Equations and StoichiometryIonic and molecular species present in

chemical systems; net-ionic equationsStoichiometry: mass and volume relations

with emphasis on the mole conceptBalancing of equations, including those

for redox reactions

7% EquilibriumConcept of dynamic equilibrium, physical

and chemical; LeChteliers principle;equilibrium constants

Quantitative treatment Equilibrium constants for gaseousreactions in terms of both molarconcentrations and partial pressure(Kc, Kp)

Equilibrium constants for reactions insolutions Constants for acids and bases; pK; pH

Solubility-product constants and theirapplication to precipitation and thedissolution of slightly solublecompounds

Constants for complex ions

Common ion effect; buffers

4% KineticsConcept of rate of reactionOrder of reaction and rate constant: their

determination from experimental dataEffect of temperature change

on ratesEnergy of activation; the role

of catalystsThe relationship between the rate-

determining step and a mechanism

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5% ThermodynamicsState functionsFirst law: heat of formation; heat ofreaction; change in enthalpy, Hesss law;heat capacity; heats of vaporization andfusionSecond law: free energy of formation;free energy of reaction; dependence ofchange in free energy on enthalpy andentropy changesRelationship of change in free energyto equilibrium constants and electrodepotentials

14% Descriptive ChemistryThe accumulation of certain specific facts ofchemistry is essential to enable students tocomprehend the development of principlesand concepts, to demonstrate applicationsof principles, to relate fact to theory andproperties to structure, and to develop anunderstanding of systematic nomenclaturethat facilitates communication. Thefollowing areas are normally included onthe examination: Chemical reactivity and products ofchemical reactions

Relationships in the periodic table:horizontal, vertical and diagonal

Chemistry of the main groups andtransition elements, including typicalexamples of each

Organic chemistry, including such topicsas functional groups and isomerism(may be treated as a separate unit or asexemplary material in other areas, suchas bonding)

9% Experimental ChemistrySome questions are based on laboratoryexperiments widely performed in generalchemistry and ask about the equipmentused, observations made, calculationsperformed, and interpretation of the results.The questions are designed to provide ameasure of understanding of the basic toolsof chemistry and their applications tosimple chemical systems.

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Sample Test Questions

The following sample questions do not appear onan actual CLEP examination. They are intendedto give potential test-takers an indication of theformat and difficulty level of the examination and toprovide content for practice and review. Knowingthe correct answers to all of the sample questionsis not a guarantee of satisfactory performance onthe exam.

Note: For all questions involving solutions and/orchemical equations, assume that the system isin pure water and at room temperature unlessotherwise stated.

Part A

Directions: Each set of lettered choices belowrefers to the numbered questions or statementsimmediately following it. Select the one letteredchoice that best answers each question or best fitseach statement. A choice may be used once, morethan once, or not at all in each set.

Questions 13

(A) F(B) S(C) Mg(D) Ar(E) Mn

1. Forms monatomic ions with 2 charge insolutions

2. Forms a compound having the formula KXO4

3. Forms oxides that are common air pollutants andthat yield acidic solutions in water

Questions 46

(A) Hydrofluoric acid(B) Carbon dioxide(C) Aluminum hydroxide(D) Ammonia(E) Hydrogen peroxide

4. Is a good oxidizing agent

5. Is used extensively for the productionof fertilizers

6. Has amphoteric properties

Questions 78

(A) A network solid with covalent bonding(B) A molecular solid with London (dispersion)

forces only(C) A molecular solid with hydrogen bonding(D) An ionic solid(E) A metallic solid

7. Solid ethyl alcohol, C2H5OH

8. Silicon dioxide, SiO2

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Questions 911

(A) CO32

(B) MnO4

(C) NH4+

(D) Ba2+

(E) Al3+

Assume that you have several unknowns,each consisting of an aqueous solution of asalt that contains one of the ions listed above.Which ion must be present if the followingobservations are made of that unknown?

9. The solution is colored.

10. An odor can be detected when a sample of thesolution is added drop by drop to a warmsolution of sodium hydroxide.

11. A precipitate is formed when a dilute solutionof H2SO4 is added to a sample of the solution.

Questions 1213

The spontaneous reaction that occurs when the cellabove operates is

2 Ag+ + Cd(s) 2 Ag(s) + Cd2+.

(A) Voltage increases.(B) Voltage decreases but remains above zero.(C) Voltage becomes zero and remains at zero.(D) No change in voltage occurs.(E) Direction of voltage change cannot be

predicted without additional information.

Which of the above occurs for each of thefollowing circumstances?

12. The silver electrode is made larger.

13. The salt bridge is replaced by a platinum wire.

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Part B

Directions: Each of the questions or incompletestatements below is followed by five suggestedanswers or completions. Select the one that is bestin each case.

14. Hydrogen Halide Normal Boiling Point, CHF +19HCl 85HBr 67HI 35

The liquefied hydrogen halides have the normalboiling points given above. The relatively highboiling point of HF can be correctly explainedby which of the following?

(A) HF gas is more ideal.(B) HF is the strongest acid.(C) HF molecules have a smaller dipole

moment.(D) HF is much less soluble in water.(E) HF molecules tend to form hydrogen bonds.

15. 1s2 2s2 2p6 3s2 3p3

Atoms of an element, X, have the electronicconfiguration shown above. The compoundmost likely formed with magnesium, Mg, is

(A) MgX(B) Mg2X(C) MgX2(D) Mg2X3(E) Mg3X2

16. The density of an unknown gas is 4.20 gramsper liter at 3.00 atmospheres pressure and127C. What is the molar mass of this gas?(R = 0.0821 liter.atm/mole.K)

(A) 14.6 g(B) 46.0 g(C) 88.0 g(D) 94.1 g(E) 138.0 g

Questions 1718

H3AsO4 + 3 I + 2 H3O

+ H3AsO3 + I3 + 3 H2O

The oxidation of iodide ions by arsenic acid inacidic aqueous solution occurs according to thebalanced equation shown above. The experimentalrate law for the reaction at 25C is

Rate = k [H3AsO4] [I] [H3O

+].

17. What is the order of the reaction with respectto I ?

(A) 1(B) 2(C) 3(D) 5(E) 6

18. According to the rate law for the reaction, anincrease in the concentration of the hydroniumion has what effect on the reaction at 25C?

(A) The rate of reaction increases.(B) The rate of reaction decreases.(C) The value of the equilibrium

constant increases.(D) The value of the equilibrium

constant decreases.(E) Neither the rate nor the value of the

equilibrium constant is changed.

19. The critical temperature of a substance is the

(A) temperature at which the vapor pressure ofthe liquid is equal to the external pressure

(B) temperature at which the vapor pressure ofthe liquid is equal to 760 mm Hg

(C) temperature at which the solid, liquid, andvapor phases are all in equilibrium

(D) temperature at which the liquid and vaporphases are in equilibrium at 1 atmosphere

(E) lowest temperature above which a substancecannot be liquefied at any applied pressure

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20. Cu(s) + 2 Ag+ Cu2+ + 2 Ag(s)

If the equilibrium constant for the reactionabove is 3.7 1015, which of the followingcorrectly describes the standard voltage, E,and the standard free energy change, G,for this reaction?

(A) E is positive and G is negative.(B) E is negative and G is positive.(C) E and G are both positive.(D) E and G are both negative.(E) E and G are both zero.

21. When 84214 Po decays, the emission consists

consecutively of an particle, then two particles, and finally another particle.The resulting stable nucleus is

(A) 83206 Bi

(B) 83210 Bi

(C) 82206 Pb

(D) 82208 Pb

(E) 81210 Tl

22. The pH of 0.1 M ammonia is approximately

(A) 1(B) 4(C) 7(D) 11(E) 14

23. . . . CrO2 + . . . OH

. . . CrO42 + . . . H2O + . . . e

When the equation for the half reaction above isbalanced, what is the ratio of the coefficientsOH : CrO2

?

(A) 1 : 1(B) 2 : 1(C) 3 : 1(D) 4 : 1(E) 5 : 1

24. CuO(s) + H2(g) Cu(s) + H2O(g) H = 2.0 kJ

The substances in the equation above are atequilibrium at pressure P and temperature T.The equilibrium can be shifted to favor theproducts by

(A) increasing the pressure by means of amoving piston at constant T

(B) increasing the pressure by adding an inertgas such as nitrogen

(C) decreasing the temperature(D) allowing some gases to escape at constant P

and T(E) adding a catalyst

25. The molality of the glucose in a 1.0 M glucosesolution can be obtained by using which ofthe following?

(A) Solubility of glucose in water(B) Degree of dissociation of glucose(C) Volume of the solution(D) Temperature of the solution(E) Density of the solution

26. The geometry of the SO3 molecule is bestdescribed as

(A) trigonal planar(B) trigonal pyramidal(C) square pyramidal(D) bent(E) tetrahedral

27. Which of the following molecules has theshortest bond length?

(A) N2(B) O2(C) Cl2(D) Br2(E) I2

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28. What number of moles of O2 is needed toproduce 14.2 grams of P4O10 (molarmass 284 g) from P?

(A) 0.0500 mole(B) 0.0625 mole(C) 0.125 mole(D) 0.250 mole(E) 0.500 mole

29. If 0.060 faraday is passed through anelectrolytic cell containing a solution of In3+

ions, the maximum number of moles of Inthat could be deposited at the cathode is


30. CH4(g) + 2 O2(g) CO2(g) + 2 H2O(l)Hrxn = 889.1 kJ mol1

Hf H2O(l) = 285.8 kJ mol1Hf CO2(g) = 393.3 kJ mol1

What is the standard heat of formation, Hf,of methane, CH4(g), as calculated from thedata above?

(A) 210.0 kJ mol1

(B) 107.5 kJ mol1

(C) 75.8 kJ mol1

(D) 75.8 kJ mol1

(E) 210.0 kJ mol1

31. Each of the following can act as both a Brnstedacid and a Brnsted base EXCEPT

(A) HCO3

(B) H2PO4

(C) NH4+

(D) H2O(E) HS

32. Two flexible containers for gases are at the sametemperature and pressure. One holds 0.50 gramof hydrogen and the other holds 8.0 grams ofoxygen. Which of the following statementsregarding these gas samples is FALSE?

(A) The volume of the hydrogen container is thesame as the volume of the oxygen container.

(B) The number of molecules in the hydrogencontainer is the same as the number ofmolecules in the oxygen container.

(C) The density of the hydrogen sample is lessthan that of the oxygen sample.

(D) The average kinetic energy of the hydrogenmolecules is the same as the average kineticenergy of the oxygen molecules.

(E) The average speed of the hydrogenmolecules is the same as the averagespeed of the oxygen molecules.

33. Pi () bonding occurs in each of the followingspecies EXCEPT

(A) CO2(B) C2H4(C) CN

(D) C6H6(E) CH4

34. 3 Ag(s) + 4 HNO3 3 AgNO3 + NO(g) + 2 H2O

The reaction of silver metal and dilute nitricacid proceeds according to the equation above.If 0.10 mole of powdered silver is added to10. milliliters of 6.0-molar nitric acid, thenumber of moles of NO gas that can beformed is


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35. Which, if any, of the following species are in thegreatest concentration in a 0.100 M solution ofH2SO4 in water?

(A) H2SO4 molecules(B) H3O

+ ions(C) HSO4

ions(D) SO4

2 ions(E) All species are in equilibrium and therefore

have the same concentrations.

36. At 20.C, the vapor pressure of toluene is 22 mmHg and that of benzene is 75 mm Hg. An idealsolution, equimolar in toluene and benzene, isprepared. At 20.C, what is the mole fraction ofbenzene in the vapor in equilibrium with thissolution?

(A) 0.23(B) 0.29(C) 0.50(D) 0.77(E) 0.83

37. Which of the following aqueous solutions hasthe highest boiling point?

(A) 0.10 M potassium sulfate, K2SO4(B) 0.10 M hydrochloric acid, HCl(C) 0.10 M ammonium nitrate, NH4NO3(D) 0.10 M magnesium sulfate, MgSO4(E) 0.20 M sucrose, C12H22O11

38. When 70 milliliters of 3.0 M Na2CO3 is addedto 30 milliliters of 1.0 M NaHCO3, the resultingconcentration of Na+ is

(A) 2.0 M(B) 2.4 M(C) 4.0 M(D) 4.5 M(E) 7.0 M

39. Which of the following species CANNOTfunction as an oxidizing agent?

(A) Cr2O72

(B) MnO4

(C) NO3

(D) S(E) I

40. A student wishes to prepare 2.00 liters of0.100 M KIO3 (molar mass 214 g). The properprocedure is to weigh out

(A) 42.8 grams of KIO3 and add 2.00 kilogramsof H2O

(B) 42.8 grams of KIO3 and add H2O until thefinal homogeneous solution has a volumeof 2.00 liters

(C) 21.4 grams of KIO3 and add H2O until thefinal homogeneous solution has a volumeof 2.00 liters

(D) 42.8 grams of KIO3 and add 2.00 litersof H2O

(E) 21.4 grams of KIO3 and add 2.00 litersof H2O

41. A 20.0-milliliter sample of 0.200 M K2CO3solution is added to 30.0 milliliters of0.400 M Ba(NO3)2 solution. Barium carbonateprecipitates. The concentration of barium ion,Ba2+, in solution after reaction is

(A) 0.150 M(B) 0.160 M(C) 0.200 M(D) 0.240 M(E) 0.267 M

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42. One of the outermost electrons in a strontiumatom in the ground state can be described bywhich of the following sets of four quantumnumbers?

(A) 5, 2, 0,12

(B) 5, 1, 1,12

(C) 5, 1, 0,12

(D) 5, 0, 1,12

(E) 5, 0, 0,12

43. Which of the following reactions does NOTproceed significantly to the right in aqueoussolutions?

(A) H3O+ + OH 2 H2O

(B) HCN + OH H2O + CN

(C) Cu(H2O)42+ + 4 NH3 Cu(NH3)42+ + 4 H2O

(D) H2SO4 + H2O H3O+ + HSO4

(E) H2O + HSO4 H2SO4 + OH

44. A compound is heated to produce a gas whosemolar mass is to be determined. The gas iscollected by displacing water in a water-filledflask inverted in a trough of water. Which of thefollowing is necessary to calculate the molarmass of the gas but does not need to be measuredduring the experiment?

(A) Mass of the compound used in theexperiment

(B) Temperature of the water in the trough(C) Vapor pressure of the water(D) Barometric pressure(E) Volume of water displaced from the flask

45. A 27.0 gram sample of an unknown hydrocarbonwas burned in excess oxygen to form 88.0 gramsof carbon dioxide and 27.0 grams of water. Whatis a possible molecular formula of thehydrocarbon?

(A) CH4(B) C2H2(C) C4H3(D) C4H6(E) C4H10

46. If the acid dissociation constant, Ka, for an acidHA is 8 104 at 25C, what percent of the acidis dissociated in a 0.50 M solution of HA at25C?

(A) 0.08%(B) 0.2%(C) 1%(D) 2%(E) 4%

47. The organic compound represented above is anexample of

(A) an alcohol(B) an aldehyde(C) an ether(D) an organic acid(E) a ketone

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48. Equal numbers of moles of H2(g), Ar(g), andN2(g) are placed in a glass vessel at roomtemperature. If the vessel has a pinhole-sizedleak, which of the following will be trueregarding the relative values of the partialpressures of the gases remaining in the vesselafter some of the gas mixture has effused?

(A) PH2 < PN2 < PAr(B) PH2 < PAr < PN2(C) PN2 < PAr < PH2(D) PAr < PH2 < PN2(E) PH2 = PAr = PN2

49. Which of the following is a correct interpretationof the results of Rutherfords experiments inwhich gold atoms were bombarded with alphaparticles?

(A) Atoms have equal numbers of positive andnegative charges.

(B) Electrons in atoms are arranged in shells.(C) Neutrons are at the center of an atom.(D) Neutrons and protons in atoms have nearly

equal mass.(E) The positive charge of an atom is

concentrated in a small region.

50. A 0.1 M solution of which of the following ionsis orange?

(A) Fe(H2O)42+

(B) Cu(NH3)42+

(C) Zn(OH)42

(D) Zn(NH3)42+

(E) Cr2O72

51. In the formation of 1.0 mole of the followingcrystalline solids from the gaseous ions, themost energy is released by

(A) NaF(B) MgF2(C) MgBr2(D) AlF3(E) AlBr3

52. If 1 mole of a nonvolatile nonelectrolytedissolves in 9 moles of water to form an idealsolution, what is the vapor pressure of thissolution at 25C? (The vapor pressure of purewater at 25C is 23.8 mm Hg.)

(A) 23.8 mm Hg

(B)910

23.8 mm Hg

(C)109

23.8 mm Hg

(D)110

23.8 mm Hg

(E) It cannot be determined from theinformation given.

53. . . . MnO4 (aq) + . . . NO2

(aq) + . . . H2O(l) . . . MnO2(s) + . . . NO3

(aq) + . . . OH (aq)

When the redox equation shown above isbalanced by using coefficients reduced to lowestwhole numbers, the coefficient for MnO4

is

(A) 1(B) 2(C) 3(D) 4(E) 6

54. If a certain solid solute dissolves in water withthe evolution of heat, which of the following ismost likely to be true?

(A) The temperature of the solution decreases asthe solute dissolves.

(B) The resulting solution is ideal.(C) The solid has a large lattice energy.(D) The solid has a large heat of fusion.(E) The solid has a large energy of hydration.

C H E M I S T R Y

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55. A 0.1-molar aqueous solution of which of thefollowing is neutral?

(A) NaNO3(B) Na2CO3(C) NH4Br(D) KCN(E) AlCl3

56. Which of the following is a true statement aboutthe halogens?

(A) Fluorine is the weakest oxidizing agent.(B) Bromine is more electronegative than

chlorine.(C) The halide ions are larger than their

respective halogen atoms.(D) Adding I2(s) to a solution containing

Br(aq) will produce Br2(l).(E) The first ionization energies increase as the

atomic number increases.

CH3CHOHCH2OH CH3CH2CH2CH3 CH3CH2CHOHCH3X Y Z

57. Considering the structures of the threecompounds, X, Y, and Z, shown above, theranking of their solubility in water from leastto greatest is which of the following?

(A) X < Y < Z(B) X < Z < Y(C) Z < Y < X(D) Y < Z < X(E) Y < X < Z

58. Of the following compounds, which is involvedin the environmental problem known as acidrain?

(A) CO2(B) CF2Cl2(C) SO2(D) H2S(E) SiO2

. . . P4O10 + . . . Ca(OH)2 . . . Ca3(PO4)2 + . . . H2O

59. When the chemical equation above is balancedin terms of lowest whole-number coefficients,the coefficient for H2O is

(A) 1(B) 2(C) 3(D) 6(E) 8

60. Which of the following best describes the role ofa catalyst in a chemical reaction?

(A) The catalyst lowers the activation energy bychanging the mechanism of the reaction.

(B) The catalyst increases the strength of thechemical bonds in the reactant molecules.

(C) The catalyst increases the value of theequilibrium constant.

(D) The catalyst provides kinetic energy toreactant molecules to increase the reactionrate.

(E) The catalyst bonds to the reaction productsand drives the equilibrium toward theproducts.

61. On the basis of trends in the periodic table, anatom of which of the following elements ispredicted to have the lowest first ionizationenergy?

(A) Ar(B) Cl(C) K(D) Rb(E) I

C H E M I S T R Y

440


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c h e m i s t r y

X(g) +Y(g) Z(g)

62. Which of the following statements is true for thechemical system represented above when thesystem has reached a state of equilibrium at aconstant temperature and pressure?

(A) The forward and reverse reactions havestopped.

(B) The forward and reverse reactions occur atthe same rate.

(C) The rate of formation of Z(g) is equal to halfthe rate of consumption of X(g).

(D) Introducing a catalyst will result in anincreased amount of Z(g) at equilibrium.

(E) Introducing moreY(g) to the system willcause more X(g) to form.

63. If a 1.0 M solution of HA, a weak acid, has a pHof 2.0, then the value of Ka, the acid-dissociationconstant, for HA is closest to

(A) 1.0 104

(B) 1.4 104

(C) 1.0 102

(D) 1.4 102

(E) 1.4 101

64. Which of the following elements is never foundpure (i.e., chemically uncombined with one ormore other elements) in Earths crust?

(A) S(B) K(C) Cu(D) Pt(E) Au

65. If an endothermic reaction occurs spontaneously,then it can be correctly inferred that

(A) a catalyst must be present(B) the reaction occurs at a slow rate(C) Grxn > 0(D) Hrxn < 0(E) Srxn > 0

66. Which of the following single covalent bonds isthe most polar?

(A) B F(B) F F(C) Cl F(D) P Br(E) Si Cl

67. In which of the following are the compoundslisted correctly in order of increasing strength oftheir oxygen-to-oxygen bonds?

(A) O2 < O3 < H2O2(B) O2 < H2O2 < O3(C) O3 < O2 < H2O2(D) H2O2 < O3 < O2(E) H2O2 < O2 < O3

68. An atom of which of the following elements hasthe smallest radius?

(A) K(B) Ca(C) Br(D) Rb(E) Sr

69. Which of the following is a Brnsted-Lowryacid-base pair?

(A) H+ and Cl

(B) Na+ and Cl

(C) HCl and NaOH(D) H2SO4 and SO4

2

(E) HCO3 and CO3

2

70. A sample of gas has a volume of 1.0 L at 300. Kand 2.0 atm. If the volume and the absolutetemperature are both doubled, what is the finalpressure of the sample?

(A) 0.50 atm(B) 1.0 atm(C) 2.0 atm(D) 4.0 atm(E) 8.0 atm

C H E M I S T R Y


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Study Resources

Most textbooks used in college-level chemistrycourses cover the topics in the outline givenearlier, but the approaches to certain topics and theemphases given to them may differ. To prepare forthe Chemistry exam, it is advisable to study one ormore college textbooks, which can be found in mostcollege bookstores. When selecting a textbook,check the table of contents against the knowledgeand skills required for this test.

Visit www.collegeboard.org/clepprep for additionalchemistry resources. You can also find suggestionsfor exam preparation in Chapter IV of the OfficialStudy Guide. In addition, many college faculty posttheir course materials on their schools websites.

C H E M I S T R Y

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Answer Key

1. B 2. E 3. B 4. E 5. D 6. C 7. C 8. A 9. B 10. C 11. D 12. D 13. C 14. E 15. E 16. B 17. A 18. A 19. E 20. A 21. C 22. D 23. D 24. C 25. E 26. A 27. A 28. D 29. B 30. C 31. C 32. E 33. E 34. A 35. B

36. D 37. A 38. D 39. E 40. B 41. B 42. E 43. E 44. C 45. D 46. E 47. E 48. A 49. E 50. E 51. D 52. B 53. B 54. E 55. A 56. C 57. D 58. C 59. D 60. A 61. D 62. B 63. A 64. B 65. E 66. A 67. D 68. C 69. E 70. C


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c h e m i s t r y

Test Measurement Overview

Format

There are multiple forms of the computer-based test,each containing a predetermined set of scoredquestions. The examinations are not adaptive. Theremay be some overlap between different forms of atest: any of the forms may have a few questions,many questions, or no questions in common. Someoverlap may be necessary for statistical reasons.

In the computer-based test, not all questionscontribute to the candidates score. Some of thequestions presented to the candidate are beingpretested for use in future editions of the tests andwill not count toward his or her score.

Scoring Information

CLEP examinations are scored without a penalty forincorrect guessing. The candidates raw score issimply the number of questions answered correctly.However, this raw score is not reported; the rawscores are translated into a scaled score by a processthat adjusts for differences in the difficulty of thequestions on the various forms of the test.

Scaled Scores

The scaled scores are reported on a scale of 2080.Because the different forms of the tests are notalways exactly equal in difficulty, raw-to-scaleconversions may in some cases differ from form toform. The easier a form is judged to be, the higherthe raw score required to attain a given scaled score.Table 1 indicates the relationship between numbercorrect (raw score) and scaled score across all forms.

The Recommended Credit-GrantingScore

Table 1 also indicates the recommendedcredit-granting score, which represents theperformance of students earning a grade of C in thecorresponding course. The recommended B-levelscore represents B-level performance in equivalentcourse work. These scores were established as theresult of a Standard Setting Study, the most recenthaving been conducted in 2007. The recommendedcredit-granting scores are based upon the judgmentsof a panel of experts currently teaching equivalentcourses at various colleges and universities. These

experts evaluate each question in order to determinethe raw scores that would correspond to B and Clevels of performance. Their judgments are thenreviewed by a test development committee, which, inconsultation with test content and psychometricspecialists, makes a final determination. Thestandard-setting study is described more fully in theearlier section entitled CLEP Credit Granting onpage 4.

Panel members participating in the most recent studywere:

Bal Barot Lake Michigan CollegeDeborah Booth University of Southern

MississippiG. Lynn Carlson University of Wisconsin

ParksideAllen Clabo Francis Marion UniversityLarry Funck Wheaton CollegeJohn Gelder Oklahoma State UniversityNoemi Jesalva Central Piedmont Community

CollegeMartha Joseph Westminster CollegePhilip Keller University of ArizonaBoon Loo Towson UniversityCraig McClure University of Alabama

BirminghamVictor Okereke SUNY Morrisville State CollegeDilip Paul Pittsburg State UniversityMargaret Reid Austin Community CollegeRichard Schwenz University of Northern ColoradoSteven Socol McHenry County CollegeDavid Stanislawski Chattanooga State Technical

Community CollegeKoni Stone California State University

StanislausLaura Strauss University of Northern IowaDuane Swank Pacific Lutheran UniversityM. Rachel Wang Spokane Falls Community

CollegeLinda Wozniewski Indiana University Northwest

To establish the exact correspondences between rawand scaled scores, a scaled score of 50 is assigned tothe raw score that corresponds to the recommendedcredit-granting score for C-level performance. Thena high (but in some cases, possibly less than perfect)raw score will be selected and assigned a scaled scoreof 80. These two points 50 and 80 determine alinear raw-to-scale conversion for the test.


20

Table 1: Chemistry Interpretive Score DataAmerican Council on Education (ACE) Recommended Number of Semester Hours of Credit: 6

* Credit-granting score recommended by ACE.Note: The number-correct scores for each scaled score on different forms may vary depending on form diffi culty.

Course Grade Scaled Score Number Correct80 68-7079 6778 6677 6576 63-6475 62-6374 61-6273 6072 5971 5870 5769 5668 54-5567 53-5466 52-53

B 65 51-5264 50-5163 4962 4861 4760 45-4659 44-4558 43-4457 42-4356 41-4255 40-4154 39-4053 3852 3751 35-36

C 50* 34-3549 33-3448 32-3347 31-3246 30-3145 29-3044 28-2943 2742 2641 24-2540 23-2439 22-2338 21-2237 20-2136 19-2035 18-1934 17-1833 1632 1531 1430 1329 11-1228 10-1127 9-1026 8-925 7-824 6-723 522 421 320 0-2


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c h e m i s t r y

Validity

Validity is a characteristic of a particular use of thetest scores of a group of examinees. If the scores areused to make inferences about the examineesknowledge of a particular subject, the validity of thescores for that purpose is the extent to which thoseinferences can be trusted to be accurate.

One type of evidence for the validity of test scores iscalled content-related evidence of validity. It isusually based upon the judgments of a set of expertswho evaluate the extent to which the content of thetest is appropriate for the inferences to be madeabout the examinees knowledge. The committeethat developed the CLEP Chemistry examinationselected the content of the test to reflect the contentof the general chemistry curriculum and courses atmost colleges, as determined by a curriculum survey.Since colleges differ somewhat in the content of thecourses they offer, faculty members should, and areurged to, review the content outline and the samplequestions to ensure that the test covers core contentappropriate to the courses at their college.

Another type of evidence for test-score validity iscalled criterion-related evidence of validity. Itconsists of statistical evidence that examinees whoscore high on the test also do well on other measuresof the knowledge or skills the test is being used tomeasure. Criterion-related evidence for the validityof CLEP scores can be obtained by studiescomparing students CLEP scores with the gradesthey received in corresponding classes, or othermeasures of achievement or ability. At a collegesrequest, CLEP and the College Board conduct thesestudies, called Admitted Class Evaluation Service, orACES, for individual colleges that meet certaincriteria. Please contact CLEP for more information.

Reliability

The reliability of the test scores of a group ofexaminees is commonly described by two statistics:the reliability coefficient and the standard error ofmeasurement (SEM). The reliability coefficient isthe correlation between the scores those examineesget (or would get) on two independent replicationsof the measurement process. The reliabilitycoefficient is intended to indicate thestability/consistency of the candidates test scores,and is often expressed as a number ranging from.00 to 1.00. A value of .00 indicates total lack ofstability, while a value of 1.00 indicates perfectstability. The reliability coefficient can be interpretedas the correlation between the scores examineeswould earn on two forms of the test that had noquestions in common.

Statisticians use an internal-consistency measure tocalculate the reliability coefficients for the CLEPexam. This involves looking at the statisticalrelationships among responses to individualmultiple-choice questions to estimate the reliabilityof the total test score. The formula used is known asKuder-Richardson 20, or KR-20, which is equivalentto a more general formula called coefficient alpha.The SEM is an index of the extent to which studentsobtained scores tend to vary from their true scores.1It is expressed in score units of the test. Intervalsextending one standard error above and below thetrue score (see below) for a test-taker will include68 percent of that test-takers obtained scores.Similarly, intervals extending two standard errorsabove and below the true score will include95 percent of the test-takers obtained scores. Thestandard error of measurement is inversely related tothe reliability coefficient. If the reliability of the testwere 1.00 (if it perfectly measured the candidatesknowledge), the standard error of measurementwould be zero.

Scores on the CLEP examination in Chemistry areestimated to have a reliability coefficient of 0.90. Thestandard error of measurement is 3.38 scaled-scorepoints.1True score is a hypothetical concept indicating what an individuals score on atest would be if there were no errors introduced by the measuring process. It isthought of as the hypothetical average of an infinite number of obtained scoresfor a test-taker with the effect of practice removed.

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