Dedicatedto
Trang 4About the Author:
Joe Mascetta has taught high school chemistry for twenty years He was the
Trang 14Introduction: About the Test
Trang 15the test is not required by the colleges to which you are applying, you can addthe result to your record to support your achievement level.
When Should You Take the Test?
You will undoubtedly do best if you take the test after completing the highschool chemistry course or courses that you plan to take At this time, thematerial will be fresh in your mind Forgetting begins very quickly after you arepast a topic or have finished the course You should plan a review program for atleast the last 6 weeks before the test date (A plan is provided later in this bookfor such a review.) Careful review definitely helps—cramming just will not do ifyou want to get the best score of which you are capable!Colleges that use SAT Subject Test results as part of the admissions processusually require that you take the test no later than December or January of yoursenior year For early-decision programs, the test time is June of your junioryear Since chemistry is often a junior year course, June of that year is theoptimum time to take the test.
When Is the Test Offered?
The chemistry test is available every time the SAT Subject Tests are given, thatis, on the first Saturday of October, November, December, May, and June Theyare also given on the last Saturday of January Be sure that the testing site forwhich you plan to register offers the SAT Subject Tests on each of these sixtimes Remember that you may choose to take one or two additional tests besideschemistry on any one test day You do have to specify in advance which testsyou plan to take on the test date you select; however, except for the LanguageTest with Listening, you may change your mind on the day of the test.
How Do You Register?
You may get all of your registration information by going to
sat.collegeboard.org/register/how to register This is the quickest and easiest
Trang 213 Mathematical calculations are limited to simple algebraic and numericalones.4 You should be familiar with the concepts of ratios and of direct and inverseproportions, scientific notation, and exponential functions.5 Metric system units are used in this test.6 The test is composed of three types of questions as explained in the nextsection.What Types of Questions Appear on the Test?There are three general types of questions on the SAT Subject Test in Chemistry— matching questions, true/false and relationship analysis questions, andgeneral five choice questions This section will discuss each type and givespecific examples of how to answer these questions You should learn thedirections for each type so that you will be familiar with them on the test day.The directions in this section are similar to those on the test.
TYPE 1 MATCHING QUESTIONS IN PART A In each of these questions,
you are given five lettered choices that you will use to answer all the questionsin that set The choices may be in the form of statements, pictures, graphs,experimental findings, equations, or specific situations Answering a questionmay be as simple as recalling information or as difficult as analyzing theinformation given to establish what you need to do qualitatively or quantitativelyto synthesize your answer The directions for this type of question specificallystate that a choice may be used once, more than once, or not at all in each set.
Part A
Directions: Every set of the given choices below refers to the numbered
Trang 22EXAMPLEQuestions 1–3 refer to the following graphs:1 The graph that best shows the relationship of volume to temperature foran ideal gas while the pressure is held constant2 The graph that best shows the relationship of volume to pressure for anideal gas while the temperature is held constant3 The graph that best shows the relationship of the number of grams ofsolute that is soluble in 100 grams of water at varying temperatures if thesolubility begins as a small quantity and increases slowly as thetemperature is increasedThese three questions require you to recall the basic gas laws and the graphicdepiction of the relationship expressed in each law, as well as how solubility canbe shown graphically.To answer question 1, you must recognize that the relationship of gas volumeto changes in temperature is a direct relationship that is depicted by graphing
Trang 24The reaction that takes place is2H2 + O2 → 2H2OThe coefficients of this gaseous reaction show that 2 L of hydrogen react with 1L of oxygen, leaving 1L of unreacted oxygen The limiting factor is the quantityof hydrogen.The ability to solve this quantitative relationship shows that statement I is nottrue However, statement II does give a true statement of the relationship ofcoefficients in a balanced equation of gaseous chemical reaction Therefore, theanswer blocks would be completed like this:EXAMPLE 2102 Water is a good solvent ofionic and polar compounds BECAUSEthe water moleculehas polar propertiesdue to the factorsinvolved in thebonding of thehydrogen and oxygenatoms.
Trang 25TYPE 3: GENERAL FIVE-CHOICE QUESTIONS IN PART C The
Trang 26(D) D(E) E
Trang 28a measure of how well you achieve on each of the three parts You will alsobecome aware of the types of questions that the test includes Use the test-scoring information following the diagnostic test to determine your raw scoreand your strengths and weaknesses in the specific areas of the test.Having taken the diagnostic test, you should then follow a study program Astudy plan covering the 6 weeks before the test has been developed for you andis given in detail on.Five Steps to Improve Your Problem-Solving Skills*
Chemistry is a subject that deals with many problem situations that you, thestudent, must be able to solve Solving problems may seem to be a naturalprocess when the degree of difficulty is not very great, and you may not need astructured method to attack these problems However, for complex problems anorderly process is required.The following is such a problem-solving process Each step is vital to the nextstep and to the final solution of the problem.Step 1 Clarify the problem: to separate the problem into the facts, theconditions, and the questions that need to be answered, and to establish thegoal.Step 2 Explore: to examine the sufficiency of the data, to organize the data,and to apply previously acquired knowledge, skills, and understanding.Step 3 Select a strategy: to choose an appropriate method to solve theproblem.Step 4 Solve: to apply the skills needed to carry out the strategy chosen.Step 5 Review: to examine the reasonableness of the solution throughestimation and to evaluate the effectiveness of the process.The steps of the problem-solving process listed above should be followed insequence The subskills listed below for each step, however, are not in sequence.The order in which subskill patterns are used will differ with the nature of theproblem and/or with the ways in which the individual problem solver thinks.Also, not every subskill need be employed in solving every problem.
Trang 31problem and can use this knowledge in a new situation In other cases,problem solvers may have to acquire needed knowledge For example, theymay solve an auxiliary problem to learn how to solve the one they arehaving difficulty with.Searching for analogous (similar) problems is a very powerful problem-solving technique When you are having difficulty with a problem, try topose a related, easier one and hope thereby to learn something that will helpyou solve the harder problem.4 SOLVE
Trang 325.12 × 105 × 3.98 × 106 divided by 910And doing all the math, you get an answer of0.02239 × 1011 or 2.24 × 109To estimate the answer, first simplify the numbers to one significant figure(significant figures are discussed in Chapter 1) This gives5 × 105 × 4 × 106 divided by 9 × 102which is20 × 1011 divided by 9 × 102 = 2.2 × 109This is the estimated answer, which validates the answer above.
Trang 33USE THIS PERIODIC TABLE WITH ALL THE PRACTICE TESTS.
* Adapted with permission from Thinking Skills Resource Guide, a
Trang 34PART 1
Trang 35A Diagnostic Test
The following test of 85 questions is a sample of the actual test you will take tomeasure your chemistry achievement It has basically the same distribution oftopics, directions, and number and types of questions Before taking this test,read the advice given in the section entitled “Final Preparation—The Day Before
the Test.” Use the answer sheet provided, and limit the test time to 1 hour.
Trang 38THE DIAGNOSTIC TESTNote: For all questions involving solutions, you should assume that the solvent iswater unless otherwise noted Reminder: You may not use a calculator on thistest!The following symbols have the meanings listed unless otherwise noted.H = enthalpy g = gram(s)M = molar J = joules(s)n = number of moles kJ = kilojoulesP = pressure L = liter(s)R = molar gas constant mL = milliliter(s)S = entropy mol = mole(s)mm = millimeter(s) T = temperatureV = volt(s) V = volumeatm = atmosphere Part A
Directions: Every set of the given lettered choices below refers to the
Trang 41Questions 22–25 refer to the following pairs of substances:(A) NH3 and N2H4(B) 16O and 17O(C) NH4Cl and NH4NO3(D) CH3OCH3 and CH3CH2OH(E) O2 and O322 Are isotopes23 Have both ionic and covalent bonds24 All allotropes25 Are strong electrolytes in aqueous solutionsPart B
Trang 52(B) CaO(C) Al2O3(D) ZnO(E) SO355 In the laboratory, 20.0 milliliters of an aqueous solution of calciumhydroxide, Ca(OH)2, was used in a titration A drop of phenolphthalein wasadded to it to indicate the end point The solution turned colorless after 20.0milliliters of a standard solution of 0.050 M HCl solution was added Whatwas the molarity of the Ca(OH)2?(A) 0.010 M(B) 0.025 M(C) 0.50 M(D) 0.75 M(E) 1.0 M56 Which of the following reactions will NOT spontaneously go tocompletion?(A) Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)
(B) CaCO3(s) + 2HCl(aq) → CaCl2(aq) + H2O(aq) + CO2(g)(C) Ag+(aq) + HCl(aq) → AgCl(s) + H+(aq)
Trang 56(A) 2NH3(g) N2(g) + 3H2(g)(B) H2(g) + Cl2(g) 2HCl(g)(C) 2NO(g) + O2(g) 2NO2(g)
Trang 59ANSWERS EXPLAINED
Trang 635 (E) The 3d subshell has 5 orbitals, or 5 possible values of m (−2, −1, 0, +1,and +2) The Pauli exclusion principle allows each orbital a maximum of 2
electrons with opposite spins So the 3d subshell can contain up to 10
Trang 6810 (C) Charles is credited with this temperature-volume relationship of gases:
Trang 8022 (B) The 16O and 17O are isotopes of the same element because they do nothave the same number of neutrons This difference in the number of
Trang 8123 (C) In NH4Cl, the covalently bonded NH4+ ion is ionically bonded to the Cl
Trang 8325 (C) Strong electrolytes will almost completely dissociate in aqueous
Trang 86103 (T, F) Ice is less dense than liquid water Water molecules, however, arepolar, not nonpolar, and water expands as these molecules arrange
Trang 93110 (T, T, CE) The first statement is true The change in Gibbs free energy, G,
depends on the enthalpy change, H, and the entropy change, S, from theequation G = H - T S Thus, statement II is also true and explains the
Trang 96113 (T, F) A pi bond is formed between p lobes of adjacent atoms and in thesame plane:
However, each p orbital consisting of two lobes can hold a total of two
Trang 97114 (T, F) The assertion that the boiling points of H2S and H2O are significantlydifferent is true, but the reason is false Water has the higher degree of
Trang 10028 (B) If the electrons have the same principal energy level, they will fill the s
Trang 10129 (A) When the chain or ring carries the full complement of hydrogen atoms,the hydrocarbon is said to be saturated The general formula for the
Trang 10634 (E) The sp3 hybrid has the tetrahedron configuration The sp2 (D) is
trigonal planar The sp (C) is linear The s (B) and p (A) are the usual
Trang 10735 (C) The reaction is
The given (8 L) and the unknown (x L) are shown above Since the
Trang 11240 (A) Dividing the percentage of each element by the atomic mass of thatelement gives the basic ratio of atoms, but not necessarily in whole
numbers Thus, (Ba) 58.8 ÷ 137 = 0.43, (S) 13.7 ÷ 32 = 0.43, (O) 27.5 ÷ 16= 1.72.
Trang 12048 (A) In the Brønsted-Lowry acid-base theory:
Trang 12452 (D)
Trang 12654 (E) Because metallic oxides are basic anhydrides, the only nonmetallicoxide is SO3 The reaction is as follows
Trang 12856 (D) All the reactions will go to completion except (D), which will not occur
Trang 13159 (E) Since in this reaction 4 volumes of gases are forming 2 volumes ofproduct, the randomness of the system is decreasing Therefore, entropy is
decreasing and S is negative In all the other reactions randomness is
Trang 13260 (D) The reaction is
Cl2 (g)+ 2Br−(excess) → 2Cl− + Br2(g)
Trang 13462 (A) HY H+ + Y−
Since [H+] is in the numerator of Ka:
Trang 13664 (B) Ksp =[Ba2+][SO42−]
If [Ba2+] = 3.9 × 10−5, then [SO42−] must also equal the same amount, so
Trang 13765 (B) H0reaction = H0f (products) − H0f (reactants)
H0reaction = −410 J − (−358 J)
Trang 14068 (C) A decrease in volume will cause the equilibrium to shift in the directionthat has less volume(s) of gas(es) In every case except (C) this is the
Trang 144CALCULATING YOUR SCORE
Trang 150remaining answers is correct Your score will be based on the number rightminus a fraction of the number answered incorrectly.4 Omit questions when you have no idea of how to answer them Youneither gain nor lose credit for questions you do not answer.5 Keep in mind that you have 1 hour to complete the test, and pace yourselfaccordingly If you finish early, go back to questions you skipped.6 Mark the answer grid clearly and correctly Be sure each answer is placedin the proper space and within the oval Erase all stray marks completely.7 Write as much as you like in the test booklet Use it as a scratch pad Onlythe answers on the answer sheet are scored for credit.D Set your alarm clock so as to allow plenty of time to dress, eat your usual(or even a better) breakfast, and reach the test center without haste oranxiety.AFTER THE TEST
After several weeks, most scores will be reported online at
www.collegeboard.org A full report will be available to you online a few days
later You can request a paper report Your score will also be mailed to your highschool and to the colleges, universities, and programs that you indicated Thereport includes your scores, percentiles, and interpretive information You canalso get your scores—for a fee—by telephone Call customer service at 866-756-7346 in the United States From outside the United States, call 212-713-7789.
If your scores are not reported by eight weeks after the test date, definitelycontact customer service by telephone or e-mail (sat@info.collegeboard.org).The mailing address for comments or questions about the tests is:
The College Board SAT ProgramP.O Box 025505