Natural Sciences CLEP PDF by Student IC

Test Information Guide: College-Level Examination Program® 2009-10 Natural Sciences

CLEP TEST INFORMATION GUIDE FOR NATURAL SCIENCES

2008-09 National CLEP Candidates by Age* Under 18 7%

History of CLEP 30 years and older 33%

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

18-22 years 37%

23-29 years 22%

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

Over the years, the CLEP examinations have evolved to keep pace with changing curricula and pedagogy. Typically, the examinations represent material taught in introductory college-level courses from all areas of the college curriculum. Students may choose from 34 different subject areas in which to demonstrate their mastery of college-level material.

2008-09 National CLEP Candidates by Gender

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

Philosophy of CLEP Promoting access to higher education is CLEP’s foundation. CLEP offers students an opportunity to demonstrate and receive validation of their college-level skills and knowledge. Students who achieve an appropriate score on a CLEP exam can enrich their college experience with higher-level courses in their major field of study, expand their horizons by taking a wider array of electives, and avoid repetition of material that they already know.

Computer-Based CLEP Testing The computer-based format of CLEP exams allows for a number of key features. These include: • a variety of question formats that ensure effective assessment • real-time score reporting that gives students and colleges the ability to make immediate creditgranting decisions (except for English Composition with Essay and, beginning July 2010, College Composition, which require faculty scoring of essays twice a month) • a uniform recommended credit-granting score of 50 for all exams • “rights-only” scoring, which awards one point per correct answer • pretest questions that are not scored but provide current candidate population data and allow for rapid expansion of question pools

CLEP Participants CLEP’s test-taking population includes people of all ages and walks of life. Traditional 18- to 22-year-old students, adults just entering or returning to school, homeschoolers, and international students who need to quantify their knowledge have all been assisted by CLEP in earning their college degrees. Currently, 60 percent of CLEP’s test-takers are women and 55 percent are 23 years of age or older. For over 30 years, the College Board has worked to provide government-funded credit-by-exam opportunities to the military through CLEP. Military service members are fully funded for their CLEP exam fees. Exams are administered at military installations worldwide through computer-based testing programs and also—in forward-deployed areas—through paper-based testing. Approximately one-third of all CLEP candidates are military service members.

CLEP Exam Development

The Committee

Content development for each of the CLEP exams is directed by a test development committee. Each committee is composed of faculty from a wide variety of institutions who are currently teaching the relevant college undergraduate courses. The committee members establish the test specifications, based on feedback from a national curriculum survey; recommend credit-granting scores and standards; develop and select test questions; review statistical data; and prepare descriptive material for use by faculty (Test Information Guides) and students planning to take the tests (CLEP Off×cial Study Guide).

The College Board appoints standing committees of college faculty for each test title in the CLEP battery. Committee members usually serve a term of up to four years. Each committee works with content specialists at Educational Testing Service to establish test specifications and develop the tests. Listed below are the current committee members and their institutional affiliations.

College faculty also participate in CLEP in other ways: they convene periodically as part of standard-setting panels to determine the recommended level of student competency for the granting of college credit; they are called upon to write exam questions and review forms; and they help to ensure the continuing relevance of the CLEP examinations through the curriculum surveys.

Edward Wells, Chair

Wilson College

Lucille Garmon

University of West Georgia

Susan Postawko

University of Oklahoma

Amy Jessen-Marshall Otterbein College The primary objective of the committee is to produce tests with good content validity. CLEP tests must be rigorous and relevant to the discipline and the appropriate courses. While the consensus of the committee members is that this test has high content validity for a typical natural sciences course or curriculum, the validity of the content for a specific course or curriculum is best determined locally through careful review and comparison of test content with instructional content covered in a particular course or curriculum.

The Curriculum Survey The first step in the construction of a CLEP exam is a curriculum survey. Its main purpose is to obtain information needed to develop test content specifications that reflect the current college curriculum and recognize anticipated changes in the field. These surveys of college faculty are conducted in each subject every three to five years depending on the discipline. Specifically, the survey gathers information on: • the major content and skill areas covered in the equivalent course, and the proportion of the course devoted to each area • specific topics taught and the emphasis given to each topic • specific skills students are expected to acquire and the relative emphasis given to them • recent and anticipated changes in course content, skills, and topics • the primary textbooks and supplementary learning resources used • titles and lengths of college courses that correspond to the CLEP exam

The Committee Meeting The exam is developed from a pool of questions written by committee members and outside question writers. All questions that will be scored on a CLEP exam have been pretested; those that pass a rigorous statistical analysis for content relevance, difficulty, fairness, and correlation with assessment criteria are added to the pool. These questions are compiled by test development specialists according to the test specifications, and presented to all the committee members for a final review. Before convening at a two- or three-day committee meeting, the members have a chance to review the test specifications and the pool of questions available for possible inclusion in the exam.

At the meeting, the committee determines whether the questions are appropriate for the test and, if not, whether they need to be reworked and pretested again to ensure that they are accurate and unambiguous. Finally, draft forms of the exam are reviewed to ensure comparable levels of difficulty and content specifications on the various test forms. The committee is also responsible for writing and developing pretest questions. These questions are administered to candidates who take the examination and provide valuable statistical feedback on student performance under operational conditions.

The American Council on Education, the major coordinating body for all the nation’s higher education institutions, seeks to provide leadership and a unifying voice on key higher education issues and to influence public policy through advocacy, research, and program initiatives. For more information, visit the ACE CREDIT Web site at www.acenet.edu/acecredit.

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

This common credit-granting score does not mean, however, that the standards for all CLEP exams are the same. When a new or revised version of a test is introduced, the program conducts a standard setting to determine the recommended credit-granting score (“cut score”).

CLEP Credit Granting CLEP uses a common recommended credit-granting score of 50 for all CLEP exams.

A standard-setting panel, consisting of 15–20 faculty members from colleges and universities across the country who are currently teaching the course, is appointed to give its expert judgment on the level of student performance that would be necessary to receive college credit in the course. The panel reviews the test and test specifications and defines the capabilities of the typical A student, as well as those of the typical B, C, and D students.* Expected individual student performance is rated by each panelist on each question. The combined average of the ratings is used to determine a recommended number of examination questions that must be answered correctly to mirror classroom performance of typical B and C students in the related course. The panel’s findings are given to members of the test development committee, who make a final determination, with the help of Educational Testing Service and College Board content and psychometric specialists, about which raw score is equivalent to B and C levels of performance.

Test SpeciÀcations Test content specifications are determined primarily through the curriculum survey, the expertise of the committee and test development specialists, the recommendations of appropriate councils and conferences, textbook reviews, and other appropriate sources of information. Content specifications take into account: • the test’s purpose • the intended test-taker population • the titles and descriptions of courses the test is designed to reflect • the specific subject matter and abilities to be tested • the length of the test, types of questions, and instructions to be used

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

Recommendation of the American Council on Education (ACE) The American Council on Education’s College Credit Recommendation Service (ACE CREDIT) has evaluated CLEP processes and procedures for developing, administering, and scoring the exams. Effective July 2001, ACE recommended a uniform credit-granting score of 50 across all subjects, with the exception of four-semester language exams, which represents the performance of students who earn a grade of C in the corresponding college course.

Natural Sciences Description of the Examination

• Qualitative and quantitative application of scientific principles (about 40 percent of the examination), including applications based on material presented in the form of graphs, diagrams, tables, equations, or verbal passages; more emphasis is given to qualitative than quantitative applications

The Natural Sciences examination covers a wide range of topics frequently taught in introductory courses surveying both biological and physical sciences at the freshman or sophomore level. Such courses generally satisfy distribution or general education requirements in science that usually are not required of nor taken by science majors. The Natural Sciences exam is not intended for those specializing in science; it is intended to test the understanding of scientific concepts that an adult with a liberal arts education should have. It does not stress the retention of factual details; rather, it emphasizes the knowledge and application of the basic principles and concepts of science, the comprehension of scientific information, and the understanding of issues of science in contemporary society.

The subject matter of the Natural Sciences examination is drawn from the following topics. The percentages next to the main topics indicate the approximate percentage of exam questions on that topic. Biological Science (50%) 10% Origin and evolution of life, classification of organisms 10% Cell organization, cell division, chemical nature of the gene, bioenergetics, biosynthesis 20% Structure, function, and development in organisms; patterns of heredity 10% Concepts of population biology with emphasis on ecology

The primary objective of the examination is to give candidates the opportunity to demonstrate a level of knowledge and understanding expected of college students meeting a distribution or general education requirement in the natural sciences. An institution may grant up to six semester hours (or the equivalent) of credit toward fulfillment of such a requirement for satisfactory scores on the examination. Some may grant specific course credit, on the basis of the total score for a two-semester survey course covering both biological and physical sciences.

Physical Science (50%) 7% Atomic and nuclear structure and properties, elementary particles, nuclear reactions 10% Chemical elements, compounds and reactions, molecular structure and bonding 12% Heat, thermodynamics, and states of matter; classical mechanics; relativity 4% Electricity and magnetism, waves, light, and sound 7% The universe: galaxies, stars, the solar system 10% The Earth: atmosphere, hydrosphere, structure features, geologic processes, and history

The examination contains approximately 120 questions to be answered in 90 minutes. Some of these are pretest questions that will not be scored. Any time candidates spend on tutorials and providing personal information is in addition to the actual testing time.

Knowledge and Skills Required The Natural Sciences examination requires candidates to demonstrate one or more of the following abilities in the approximate proportions indicated. • Knowledge of fundamental facts, concepts, and principles (about 40 percent of the examination) • Interpretation and comprehension of information (about 20 percent of the examination) presented in the form of graphs, diagrams, tables, equations, or verbal passages

N A T U R A L

S C I E N C E S

The examination includes some questions that are interdisciplinary and cannot be classified in one of the listed categories. Some of the questions cover topics that overlap with those listed previously, drawing on areas such as history and philosophy of science, scientific methods, science applications and technology, and the relationship of science to contemporary problems of society, such as environmental pollution and depletion of natural resources. Some questions are laboratory oriented.

Questions 3–5

(A)

(D)

(E)

(B)

Sample Test Questions The following sample questions do not appear on an actual CLEP examination. They are intended to give potential test-takers an indication of the format and difficulty level of the examination and to provide content for practice and review. Knowing the correct answers to all of the sample questions is not a guarantee of satisfactory performance on the exam.

(C)

Directions: Each group of questions that follow consists of five lettered choices followed by a list of numbered phrases or sentences. For each numbered phrase or sentence, select the one choice that is most clearly related to it. Each choice may be used once, more than once, or not at all in each group.

3. A sample of gas remains at constant temperature. Vertical axis: Volume of the sample Horizontal axis: Pressure on the sample 4. An object moves at constant speed. Vertical axis: Distance traveled since time t = 0 Horizontal axis: Time

Questions 1–2 (A) Cell wall (B) Cell membrane (C) Nucleus (D) Mitochondrion (E) Ribosome

5. A constant unbalanced force acts on an object. Vertical axis: Acceleration of the object Horizontal axis: Time Questions 6–7

1. The chief site of energy production in the cell (A) Tuberculosis (B) Phenylketonuria (C) Huntington chorea (D) Cystic fibrosis (E) Tay-Sachs disease

2. The site of protein synthesis in the cell

6. The disease that is NOT genetically inherited 7. The disease that can be controlled merely through regulation of diet

N A T U R A L

S C I E N C E S

Directions: Each of the questions or incomplete statements below is followed by five suggested answers or completions. Select the one that is best in each case.

Questions 10–11 In fruit flies, “straight wings” (S) is dominant over “curly wings” (s), and gray body color (G) is dominant over black body color (g). A straightwinged female with gray body color was mated with a straight-winged male with black body color and the following ratios of offspring resulted. The experiment was conducted at 25°C.

8. As a direct result of photosynthesis, energy is stored in molecules of which of the following? (A) RNA (B) DNA (C) C6H12O6 (glucose) (D) H2O (E) CO2

Ratio

Phenotype

3/8

straight-winged; gray body color

3/8

straight-winged; black body color

1/8

curly-winged; gray body color

1/8

curly-winged; black body color

9. A person whose gallbladder has been removed has a decreased ability to store bile and therefore to digest 10. The data above suggest that the genotype of the male parent is

(A) fats (B) starches (C) sugars (D) proteins (E) vitamins

(A) SsGg (B) SSGg (C) ssgg (D) Ssgg (E) ssGg 11. The data above suggest that the genotype of the offspring with curly wings and black body color is (A) SsGg (B) SSGg (C) ssgg (D) Ssgg (E) ssGg 12. The classification characteristics that define the genus of an animal or a plant are usually more general than those defining (A) a class (B) an order (C) a species (D) a family (E) a phylum

N A T U R A L

S C I E N C E S

13. Hard water is undesirable and is often softened because hard water

17. In embryonic origin, nerve cells are most similar to

(A) is too viscous for regular uses (B) contains trace amounts of toxic substances (C) forms insoluble precipitates when boiled or when used with soap (D) cannot be used efficiently by the body due to dissolved impurities (E) evaporates more rapidly than soft water

(A) epidermal cells (B) bone cells (C) red blood cells (D) liver cells (E) reproductive cells 18. In the name Homo sapiens, the word sapiens refers to the

14. Which of the following adaptations is more likely to be found in the leaves of desert plants than in those of plants that grow in moist regions?

(A) species (B) family (C) class (D) genus (E) order

(A) Stomata mostly on upper leaf surface (B) A thin, transparent cuticle (C) A smooth leaf surface free of hairs (D) A thickened epidermis and cuticle (E) A loosely packed mesophyll layer 15. If all the xylem from a section of tree trunk could be removed, which of the following would most likely happen first? (A) Food could not pass from the leaves to the roots. (B) The roots would be unable to transfer any stored food to the spring buds. (C) The leaves would be unable to get any carbon dioxide. (D) The roots would be unable to store food. (E) The leaves would be unable to get sufficient water.

19. A student placed a sprig of green water plant under a funnel in a glass vessel full of water and then placed a test tube full of water mouthdownward over the stem of the funnel. After the setup had been exposed to sunlight for several hours, the student tested a gas that had collected in the test tube and concluded that the plant had produced oxygen. The results of this experiment could have been interpreted more satisfactorily if

16. Whereas the ultimate source of energy for most organisms is sunlight, the immediate source is (A) chemical (B) electrical (C) thermal (D) gravitational (E) radiant

(A) the water had been tested for carbon dioxide (B) only the leaves of the plant had been used (C) air had been forced through the water (D) the plant had not been exposed to sunlight (E) a similar experiment had been set up without sunlight

N A T U R A L

S C I E N C E S

20. Which of the following best completes the statement below?

24. In many cultivated plants (such as oranges, bananas, and potatoes), favorable characteristics often are created by careful genetic crosses. Of the following, which would be the best way to maintain the traits of a new variety with favorable characteristics?

Among multicellular animals, the insects exhibit the greatest diversity of life-forms; therefore ______.

(A) Selfing individuals of this new variety (i.e., crossing the offspring of one parental plant) (B) Artificially pollinating wild varieties with pollen from the new variety (C) Artificially pollinating the new variety with pollen from wild varieties (D) Crossing the new variety with a variety that was homozygous recessive for all traits of concern (E) Vegetative reproduction of the new variety

(A) the total number of insect species is limited (B) the presence of wings on an insect is probably an evolutionary error (C) insects probably occupy the greatest number of niches (D) insect control by human beings is simplified (E) any genetic mutation in fruit flies is likely to escape detection 21. The percentage of phosphates in commercial detergents was reduced primarily because phosphates were shown to

25. In mammals, insulin is produced in which of the following structures?

(A) be less effective cleaning agents than most other compounds (B) build up in animal tissues and cause sterility (C) cause cancer in animals (D) cause birth defects in animals (E) increase the growth rates of algae in lakes and rivers

(A) Pancreas (B) Liver (C) Salivary glands (D) Hypothalamus (E) Pituitary gland 26. Which of the following occurs during anaphase I of meiosis?

22. Carbohydrates are most commonly stored in plants in the form of

(A) The sister chromatids are pulled to opposite poles of the spindle. (B) The spindle apparatus forms. (C) The nuclear envelope disintegrates. (D) The centromeres replicate. (E) The homologous pairs of chromosomes separate.

(A) starch (B) cellulose (C) lactose (D) ribose (E) sucrose 23. A father will transmit the genes of his Y chromosome to

27. All living cells have which of the following structures?

(A) one-half of his sons only (B) one-half of his daughters only (C) all of his sons only (D) all of his daughters only (E) none of his sons

(A) Endoplasmic reticulum (B) Nucleus (C) Plasma membrane (D) Cilia (E) Vacuole

N A T U R A L

S C I E N C E S 32. Which of the following most directly leads to changes in cellular specialization during embryonic development?

28. Digestion of proteins in mammals begins in which of the following organs? (A) Mouth (B) Stomach (C) Small intestine (D) Colon (E) Gallbladder

(A) Meiosis in the embryo’s cells (B) Changes in the environmental stimuli the embryo experiences in the uterus (C) Formation of the placenta (D) An increase in the amount of DNA in the embryo due to replication (E) Changes in gene expression

29. Which of the following terrestrial biomes typically has the greatest species diversity?

33. Which of the following animals is most closely related to the cheetah?

(A) Tundra (B) Taiga (C) Deciduous forest (D) Chaparral (E) Tropical rain forest

(A) Chicken (B) Alligator (C) Frog (D) Squirrel (E) Eagle

30. Which of the following instruments would be most useful for studying the internal structure of a chloroplast? (A) Transmission electron microscope (B) Scanning electron microscope (C) Compound light microscope (D) Dissecting microscope (E) Phase-contrast microscope

34. Which of the following organisms transmits the West Nile virus to humans? (A) Housefly (B) Tsetse fly (C) Mosquito (D) Tick (E) Mouse

31. A hawk can have which of the following ecological roles? I. Primary consumer II. Secondary consumer III. Tertiary consumer

35. A photosynthetic eukaryotic cell typically contains (A) chloroplasts only (B) mitochondria only (C) both chloroplasts and mitochondria (D) either chloroplasts or mitochondria, but never both at once (E) neither chloroplasts nor mitochondria

(A) I only (B) II only (C) III only (D) I and II only (E) II and III only

N A T U R A L 36. A theory fails to meet the criteria of scientific methodology if

S C I E N C E S 40. Which of the following best describes the principal way in which Earth’s atmosphere is heated?

(A) it is unpopular (B) it contradicts other theories (C) it has not been conclusively proved (D) it has not been stated in mathematical terms (E) no experiments can be designed to test it

(A) Heat flows from the center of Earth and is conducted through the ground to the air. (B) The atmosphere absorbs short-wave radiation from the Sun as the Sun’s rays pass through it. (C) Earth absorbs short-wave radiation from the Sun and reradiates long-wave radiation, which is absorbed by the atmosphere. (D) The air absorbs short-wave radiation from the Sun after the radiation has been reflected by the clouds. (E) Warm air rises and cold air sinks and, as it sinks, is warmed by compression.

37. Dark lines in the Sun’s spectrum are explained as resulting from (A) emission of radiation of certain frequencies from the Sun’s atmosphere (B) absorption of energy by atoms in the outer layers of the Sun (C) radiation of ultraviolet light from sunspots (D) continuous radiation from the corona (E) x-rays emanating from the Sun’s atmosphere

41. Most of Earth’s water exists in (A) the oceans (B) the atmosphere (C) groundwater (D) lakes and rivers (E) polar ice caps

38. Scientists estimate the age of the Sun to be about (A) 100 billion years (B) 25 billion years (C) 14 billion years (D) 4.6 billion years (E) 3.8 billion years 39. Sunspots on the surface of the Sun are correlated with which of the following?

42. If the present electric power needs of the United States are to be provided by solar power only, all the sunlight incident on which of the following areas must be collected? (Assume 100 percent efficiency.) (A) A small percent of the area in the United States (B) All of the area in the United States (C) All of the area in the Western Hemisphere (D) All of the area of Earth (E) All of the area of Earth plus some in outer space

(A) Relatively low temperatures compared with the surrounding surface (B) Relatively high temperatures compared with the surrounding surface (C) Periods of low solar activity (D) Fusion of helium nuclei rather than hydrogen nuclei (E) The warming of ocean surface waters in the eastern Pacific (El Niño)

N A T U R A L 43. Which of the following natural resources is NOT a fossil fuel?

S C I E N C E S 47. The half-life of 146 C is 5,600 years. Which of the following statements about a 10-gram sample of 14 6 C is correct?

(A) Uranium (B) Natural gas (C) Petroleum (D) Anthracite coal (E) Bituminous coal

(A) The radioactive decay of the sample will be complete after 5,600 years. (B) The 146 C sample will start radioactive decay after 5,600 years. (C) A time of 5,600 years has been required to produce this sample of 146 C in nature. (D) After 5,600 years the sample will contain only 5 grams of 146 C. (E) After 11,200 years the sample will not contain any 146 C.

44. All of the following geologic time intervals are characterized correctly EXCEPT (A) Cambrian period . . . age of birds (B) Carboniferous period . . . age of amphibians (C) Devonian period . . . age of fishes (D) Cenozoic era . . . age of mammals (E) Mesozoic era . . . age of dinosaurs

48. Impact craters dominate the Moon’s surface, yet are rare on Earth’s surface. Reasons for this difference include which of the following? I. The Moon has no atmosphere. II. The Moon is geologically inactive. III. The Moon is much older.

45. Which of the following is the farthest, on average, from Earth? (A) Andromeda galaxy (B) Halley’s comet (C) Jupiter (D) Sirius (E) Uranus CaO + CO2 ĺ CaCO3 46. What mass of CaO is needed to absorb 22 grams of CO2 according to the balanced chemical equation above? (Molar masses: CaO = 56 g/mol, CO2 = 44 g/mol)

(A) I only (B) II only (C) I and II only (D) II and III only (E) I, II, and III 49. At a fixed pressure, when the temperature of a gas sample increases, its volume increases. This relationship between the temperature and the volume of a gas is best described as which of the following? (A) Direct proportion (B) Inverse proportion (C) Limiting ratio (D) Hyperbolic function (E) Logarithmic function

(A) 112 g (B) 100 g (C) 56 g (D) 28 g (E) 22 g

N A T U R A L 50. The notation 1s2 2s2 2p4 represents (A) a noble gas (B) an atomic nucleus (C) an element with atomic mass 8 (D) an element with atomic number 8 (E) an element with an oxidation state of 4

S C I E N C E S 53. Of the following planets that are visible with the naked eye—Venus, Mars, Jupiter, and Saturn— only Venus has an orbit smaller than that of Earth. This means that Venus (A) is seen only in the morning or the evening sky (B) can be seen in the sky near midnight more often than at other times (C) can rarely be seen at all (D) has an orbit that is more elliptical than that of Earth (E) has a longer year than Earth

51. Which of the following molecules can have more than one equivalent Lewis structure? (A) H

(B) H C (C) O

C H

54. Which of the following is NOT generally true of metals? (A) They are usually solid at room temperature. (B) They are good conductors of heat and electricity. (C) They easily form negative ions. (D) They have luster. (E) They can be hammered into sheets or rolled into wires.

(D) H N H H

H (E) H C O H H

55. Within molecules of a compound, atoms are held together by chemical bonds that are primarily

52. In old-fashioned flashbulbs, light was produced by the reaction of magnesium metal, Mg, sealed in the bulb with oxygen gas, O2. After the flash, the mass of the sealed bulb was (A) definitely greater than it was before use (B) definitely smaller than it was before use (C) essentially the same as it was before use (D) greater or smaller depending on the amount of O2 consumed (E) greater or smaller depending on the amount of light produced

(A) thermal (B) frictional (C) gravitational (D) electrostatic (E) magnetic 56. An unsorted mixture of clay, boulders, sand, and silt would most likely be deposited from which of the following? (A) Glacial ice (B) Subsurface water (C) Streams (D) Waves (E) Wind

N A T U R A L 57. Valleys with U-shaped cross sections are the result of erosion by which of the following?

S C I E N C E S 60. Which of the following correctly identifies the 131 constituents of an atom of the isotope 53 I ?

(A) Glaciers (B) Perennial streams (C) Intermittent streams (D) Mudflows (E) Wind d

(A) (B) (C) (D) (E)

Protons 53 78 53 78 131

Neutrons 78 53 78 131 53

Electrons 78 78 53 78 53

61. Which of the following types of electromagnetic radiation has photons of the LEAST energy? X

(A) Visible light (B) Ultraviolet light (C) Microwaves (D) Gamma radiation (E) Radio waves

58. The balance shown above is in equilibrium at Earth’s surface, and the two arms have the same length d. Thus the two objects, X and Y (not necessarily drawn to scale), must have identical (A) densities (B) masses (C) shapes (D) specific gravities (E) volumes

62. The atomic mass of carbon is 12 and the atomic mass of hydrogen is 1. What is the percent by mass of carbon in methane gas, CH4? (A) 20% (B) 25% (C) 50% (D) 75% (E) 80%

59. On a global basis, for which of the following activities is the most water used each day? (A) Crop irrigation (B) Cooling in power plants (C) Commercial laundering (D) Manufacturing of textiles (E) Production of steel

63. Southern California experienced an earthquake that registered magnitude 3.5 on the Richter scale. One month later the same area experienced an earthquake that registered 5.5. About how many times as much energy was released by the magnitude 5.5 earthquake than by the magnitude 3.5 earthquake? (A) 2 (B) 10 (C) 200 (D) 1,000 (E) 2,000

N A T U R A L

S C I E N C E S

64. The study of which of the following would likely be the most helpful in providing information about the composition of Earth’s upper mantle? (A) Temperatures of hot springs (B) Size of vesicles in basalt flows (C) Xenolith inclusions in igneous rocks (D) Carbonate sediments from the ocean floor (E) Minerals formed through contact metamorphism

67. The amount of heat energy released when a certain type of candle is burned is 48,000 joules per gram of wax consumed. Which of the following expressions is equal to the number of grams of wax that need to be burned in order to raise the temperature of 500 grams of water from 20°C to 30°C, assuming all the heat released goes into heating the water? (The specific heat of water is 4.19 J/g°C.) (48, 000)(10)(4.19) 500 (48, 000)(4.19) (B) (500)(10)

(A)

65. Which of the following are found in greater number in the nuclei of carbon-14 atoms than in the nuclei of carbon-12 atoms? (A) Alpha particles (B) Positrons (C) Neutrons (D) Protons (E) Electrons 66. Which of the following best describes the motion of winds within large storm systems in the Northern Hemisphere?

(C)

(4.19)(10)(500) 48, 000

(D)

(4.19)(500) (10)(48, 000)

(E) (30)(4.19)(500) (20)(48, 000) 68. Which of the following types of radiation is typically produced in the laboratory by a high-voltage electron beam impacting a metallic target? (A) Primary cosmic radiation (B) X-ray radiation (C) Neutron radiation (D) Ultraviolet radiation (E) Beta radiation

(A) North to south (B) West to east (C) Southwest to northeast (D) Clockwise (E) Counterclockwise

N A T U R A L Questions 69–71 CuO + H2 ĺ Cu + H2O

S C I E N C E S 71. Which of the following would most likely increase the effectiveness of the hydrogen gas reducing the copper(II) oxide? (A) Heating the test tube (B) Cooling the test tube (C) Putting the test tube under reduced pressure (D) Filling the test tube with dilute HCl solution (E) Filling the test tube with dilute NaOH solution

The drawing below depicts an apparatus for reducing copper(II) oxide to the metal by the reaction above.

Thistle Tube Test Tube Drying Tube

72. Which of the following typically occurs when a forested watershed is clear-cut? Rubber Stoppers

(A) Annual rainfall increases. (B) Soil erosion increases. (C) The water temperature in streams decreases. (D) The sediment load in streams decreases. (E) Atmospheric concentration of O2 increases.

Copper(II) Oxide 250-mL. Erlenmeyer Flask

Zinc

69. In order to produce a stream of hydrogen gas for this reaction, one should add which of the following through the thistle tube?

73. Which characteristic of a star most directly relates to the likelihood of that star’s eventually becoming a black hole?

(A) Water (B) Dilute hydrochloric acid (C) Dilute copper(II) sulfate solution (D) Hydrogen peroxide (E) Dilute ammonia solution

(A) Apparent magnitude (B) Absolute magnitude (C) Surface temperature (D) Diameter (E) Mass

70. After the production of hydrogen gas starts, withdrawing the thistle tube would result in which of the following? (A) Moisture would collect in the flask. (B) The evolution of hydrogen gas would stop. (C) Much hydrogen gas would escape without coming in contact with the copper oxide. (D) Air would enter the flask faster than hydrogen gas would be evolved. (E) The rate of production of hydrogen gas would increase.

N A T U R A L 74. How many joules of energy are absorbed by a 20.0 g sample of water as the temperature of the sample is raised from 273 K to 283 K? (The specific heat capacity of water is 4.2 J g−1K−1.) (A) 42 J (B) 84 J (C) 200 J (D) 840 J (E) 4,200 J

S C I E N C E S 2 NO2(g) M N2O4(g) 75. The equation above represents a system that has reached a state of chemical equilibrium. Which of the following is a true statement about the system? (A) All chemical reaction rates have dropped to zero. (B) The system will eventually contain only N2O4 molecules. (C) The concentration of NO2(g) must be twice that of N2O4(g). (D) The concentration of NO2(g) must be less than that of N2O4(g). (E) N2O4 molecules are being consumed as fast as they are produced.

N A T U R A L

S C I E N C E S

Study Resources

Answer Key

Most textbooks used in college-level natural sciences courses cover the topics in the outline given earlier, but the approaches to certain topics and the emphases given to them may differ. To prepare for the Natural Sciences exam, it is advisable to study one or more college textbooks (selecting at least one biological science and one physical science textbook), which can be found in most college bookstores. When selecting a textbook, check the table of contents against the knowledge and skills required for this test.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37.

If candidates maintain an interest in scientific issues; read science articles in newspapers and magazines; watch educational television programs on scientific topics; or work in fields that require a knowledge of certain areas of science, such as nursing and laboratory work, they will probably be knowledgeable about many of the topics included on the Natural Sciences exam. Visit www.collegeboard.com/clepprep for additional science resources. You can also find suggestions for exam preparation in Chapter IV of the Official Study Guide. In addition, many college faculty post their course materials on their schools’ Web sites.

D E C D E A B C A D C C C D E A A A E C E A C E A E C B E A E E D C C E B

38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75.

D A C A A A A A D D C A D C C A C D A A B A C E D D C C E C B B C A B E D E

N A T U R A L

Test Measurement Overview Format There are multiple forms of the computer-based test, each containing a predetermined set of scored questions. The examinations are not adaptive. There may be some overlap between different forms of a test: any of the forms may have a few questions, many questions, or no questions in common. Some overlap may be necessary for statistical reasons. In the computer-based test, not all questions contribute to the candidate’s score. Some of the questions presented to the candidate are being pretested for use in future editions of the tests and will not count toward his or her score.

Scoring Information CLEP examinations are scored without a penalty for incorrect guessing. The candidate’s raw score is simply the number of questions answered correctly. However, this raw score is not reported; the raw scores are translated into a scaled score by a process that adjusts for differences in the difficulty of the questions on the various forms of the test.

Scaled Scores The scaled scores are reported on a scale of 20–80. Because the different forms of the tests are not always exactly equal in difficulty, raw-to-scale conversions may in some cases differ from form to form. The easier a form is judged to be, the higher the raw score required to attain a given scaled score. Table 1 indicates the relationship between number correct (raw score) and scaled score across all forms.

The Recommended Credit-Granting Score

S C I E N C E S test content and psychometric specialists, makes a final determination. The standard-setting study is described more fully in the earlier section entitled “CLEP Credit Granting” on page 4. Panel members participating in the most recent study were: Joseph Allen Brenda Alston-Mills Bruce Callen Amber Charlebois Thomas Cobb Jean DeSaix Norman Derby Ginger Fisher Amy Gort Terry Jones Philip Keller Frank Kuserk Jorge Lopez Victor Okereke Susan Postawko Zachary Senwo Rainy Shorey Linda Wozniewski

Concord University North Carolina State University Drury University William Patterson University Bowling Green State University University of North Carolina— Chapel Hill Bennington College Wilson College Concordia University— St. Paul California State University— Stanislaus University of Arizona Moravian College University of Texas—El Paso SUNY Morrisville State College University of Oklahoma Alabama A&M University Ferris State University Indiana University—Northwest

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

Table 1 also indicates the recommended credit-granting score, which represents the performance of students earning a grade of C in the corresponding course. The recommended B-level score represents B-level performance in equivalent course work. These scores were established as the result of a Standard Setting Study, the most recent having been conducted in 2006. The recommended credit-granting scores are based upon the judgments of a panel of experts currently teaching equivalent courses at various colleges and universities. These experts evaluate each question in order to determine the raw scores that would correspond to B and C levels of performance. Their judgments are then reviewed by a test development committee, which, in consultation with

Table 1: Natural Sciences Interpretive Score Data American Council on Education (ACE) Recommended Number of Semester Hours of Credit: 6 Course Grade

Scaled Score

Number Correct

80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50* 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20

100 98–99 96-97 94-96 93-94 91-92 89-91 88-89 86-88 85-86 83-85 81-83 80-81 78-80 77-78 75-77 74-75 72-74 71-72 69-70 67-69 66-67 64-66 63-64 61-63 60-61 58-59 57-58 55-56 54-55 52-53 51-52 49-50 48-49 46-47 44-46 43-44 41-42 40-41 38-39 37-38 35-36 34-35 32-33 31-32 29-30 28-29 26-27 24-26 23-24 21-23 20-21 18-20 17-18 15-17 14-15 12-13 10-12 9-10 7-9 0-7

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

N A T U R A L

S C I E N C E S

Validity

Reliability

Validity is a characteristic of a particular use of the test scores of a group of examinees. If the scores are used to make inferences about the examinees’ knowledge of a particular subject, the validity of the scores for that purpose is the extent to which those inferences can be trusted to be accurate.

The reliability of the test scores of a group of examinees is commonly described by two statistics: the reliability coefficient and the standard error of measurement (SEM). The reliability coefficient is the correlation between the scores those examinees get (or would get) on two independent replications of the measurement process. The reliability coefficient is intended to indicate the stability/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 of stability, while a value of 1.00 indicates perfect stability. The reliability coefficient can be interpreted as the correlation between the scores examinees would earn on two forms of the test that had no questions in common.

One type of evidence for the validity of test scores is called content-related evidence of validity. It is usually based upon the judgments of a set of experts who evaluate the extent to which the content of the test is appropriate for the inferences to be made about the examinees’ knowledge. The committee that developed the CLEP Natural Sciences examination selected the content of the test to reflect the content of the general natural sciences curriculum and courses at most colleges, as determined by a curriculum survey. Since colleges differ somewhat in the content of the courses they offer, faculty members should, and are urged to, review the content outline and the sample questions to ensure that the test covers core content appropriate to the courses at their college. Another type of evidence for test-score validity is called criterion-related evidence of validity. It consists of statistical evidence that examinees who score high on the test also do well on other measures of the knowledge or skills the test is being used to measure. Criterion-related evidence for the validity of CLEP scores can be obtained by studies comparing students’ CLEP scores with the grades they received in corresponding classes, or other measures of achievement or ability. At a college’s request, CLEP and the College Board conduct these studies, called Admitted Class Evaluation Service, or ACES, for individual colleges that meet certain criteria. Please contact CLEP for more information.

Statisticians use an internal-consistency measure to calculate the reliability coefficients for the CLEP exam. This involves looking at the statistical relationships among responses to individual multiple-choice questions to estimate the reliability of the total test score. The formula used is known as Kuder-Richardson 20, or KR-20, which is equivalent to a more general formula called coefficient alpha. The SEM is an index of the extent to which students’ obtained scores tend to vary from their true scores.1 It is expressed in score units of the test. Intervals extending one standard error above and below the true score (see below) for a test taker will include 68 percent of that test taker’s obtained scores. Similarly, intervals extending two standard errors above and below the true score will include 95 percent of the test taker’s obtained scores. The standard error of measurement is inversely related to the reliability coefficient. If the reliability of the test were 1.00 (if it perfectly measured the candidate’s knowledge), the standard error of measurement would be zero. Scores on the CLEP examination in Natural Sciences are estimated to have a reliability coefficient of 0.91. The standard error of measurement is 2.48 scaled-score points. 1

True score is a hypothetical concept indicating what an individual’s score on a test would be if there were no errors introduced by the measuring process. It is thought of as the hypothetical average of an infinite number of obtained scores for a test taker with the effect of practice removed.

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