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Information about 1st ACS Exam (Part of the Final Exam)—More Calculation Intensive Exam
The exam has 70 questions to be answered in 120 minutes. The topical breakdown is as follows.
of Q’s Topic PS’s Section (page number) in ACS Guide
5 Measurements^ (Uncertainty, Sig. Figs, Accuracy, Precision, Density)
PS1 no particular section, maybe a bit in Descriptive Chemistry/Periodicity (p. 91)
Nanoscopic Pictures , Classification of Matter , Atomic Structure-I (Isotopic Symbols, Abundance), Intro to Periodic Table
PS1, PS2, and PS4 (parts of)
Atomic Structure (p. 1) States of Matter/Solutions (p. 31) Descriptive Chemistry/Periodicity (p. 91) ??
7 Nomenclature^ and Formulas of Ionic and Binary Molecular Compounds
PS3 no particular section? stoich?
Stoichiometry-I (“interconversions”, equations [balancing and utilizing], EF and MF, combustion analysis, LR, % Yield) – NO molarity or gases
PS4, PS5 Stoichiometry (p. 21)
Aqueous Solutions (molarity, electrolytes) and Reactions (acid- base and redox), including titrations and net ionic equations
PS5, PS
States of Matter/Solutions (p. 31) Stoichiometry (p. 21)
5 Gases PS7 States of Matter/Solutions (p.31) 6 Thermochemistry PS8 Energetics (p. 43), PARTIAL
Atomic Structure-II (Light [waves, photons], Emission & Absorption, Orbitals, Configurations)
PS9 Atomic Structure (p. 1)
3 Periodic Properties (& Shell Model) PS10 Descriptive Chemistry/Periodicity (p. 91)
Molecular Structure-Bonding (LDS, FC, resonance structures, bond order/strength/length, VSEPR, polarity, hybridization)
PS10, PS11 Molecular Structure and Bonding (p. 11) & States of Matter/Solutions (p. 31)
2 Liquids and Solids^ (IM Forces, Types of Solids)
PS12 Molecular Structure and Bonding (p. 11) & States of Matter/Solutions (p. 31)
Information about 2nd^ ACS Exam (Part of the Final Exam)—More Conceptually Intensive Exam
The exam has 40 questions to be answered in 55 minutes. The topical breakdown is as follows.
of Q’s Topic PS’s Section (page number) in ACS Guide
6 Properties of Matter 1 States of Matter/Solutions (p.31) 2 Atoms, Elements, and Compounds [Includes Dalton's Theory, early Laws; Nanoscopic pictures, etc.]
2, 3 Stoichiometry (p. 21)
6 Gases 7 States of Matter/Solutions (p. 31) 4 Solutions and Concentration 5, 6, 13 States of Matter/Solutions (p.31) 10 Stoichiometry 4, 5, 6, 7 Stoichiometry (p. 21) 2 Atomic Structure 2, 9, 10, 11 Atomic Structure (p. 1)
Molecular Structure [Includes IM forces, liquids and solids]
Molecular Structure and Bonding (p. 11) & States of Matter/Solutions (p. 31)
2 Thermochemistry 8 Energetics (p. 43)
NOTE #1 : To any of you that are using the ACS preparation book, either the one you purchased or a reserve copy in the library, be aware that you need only look at certain sections in this book (Sections 6, 7, 8, and 10 are not for first- semester exams and should be completely skipped by you; parts of 5 and 9 are second-semester topics as well, but some topics there (actually most of section 5) are first-semester topics). To help you study, I have specified in the table the sections in the ACS book that I believe apply to the topics given. For example, "thermochemistry" will be found in the section entitled "Energetics" (section 5). Be aware that there may be some topics in a given chapter that
we have not discussed. In general, do NOT worry about these other topics! For example, in the chapter on "Energetics", "entropy" (symbol S) and "free energy" (symbol G) are discussed, but they are NOT covered on this exam (despite what is written in the "How to Use This Book" section). In that chapter you need "only" understand concepts and questions pertaining to "enthalpy" (symbol H) and specific heat, etc, since those are what thermochemistry involves.
NOTE #2 : The ACS book is certainly helpful, but do not view it as the "end-all be-all" source of what to study! Remember that there is a supplemental part including questions from ME! Some topics that we have discussed are not in the ACS book (it's a pretty small book compared to our text!). I obviously believe that if you fully understand what's in my answer keys, you will be very well prepared for this exam. The ACS book is useful primarily in giving you an opportunity to see questions that are in a similar format to what will be on the exam. (Also, I think that the authors of the ACS book make the same mistake that most of the textbooks do in not properly defining the meaning of the coefficients in a chemical equation; this book should not be seen as "perfect" or "complete" in any way!)
The following Tables will appear on the inside front cover of the exam. Be aware that this sheet is the same for ALL ACS exams (for both semesters of General Chemistry, e.g.,), so quite a bit of the information relates to ideas or topics that will not be needed on the exam that you will take.
- Which phenomenon can be explained by assuming strong hydrogen bonding?
A. Ca reacts with H 2 to form CaH (^) 2. B. H 2 reacts with Cl 2 to form 2HCl. C. The boiling point of water is higher than that of H 2 S. D. The boiling point of C 7 H 16 is higher than that of C 3 H (^) 8. E. The boiling point of H 2 Se is higher than that of H 2 S.
- The formula of sodium vanadate is Na 3 VO 4 and that of calcium chloride is CaCl 2. What is the formula of calcium vanadate?
A. CaVO (^4) B. Ca(VO 4 ) (^2) C. Ca(VO 4 ) (^3) D. Ca 3 (VO 4 ) (^2) E. Ca 2 VO (^4)
- Balance the equation for the following reaction, using no fractional coefficients
? C +? HNO 3 →? CO 2 +? NO 2 +? H 2 O
The sum of the coefficients in the balanced equation is
A. 5 B. 7 C. 9 D. 12 E. 16
- The ions present in solid silver chromate Ag 2 CrO 4 are
A. Ag+ and CrO 4 2- B. Ag 2+^ and CrO 4 4- C. Ag+, Cr 6+^ , and O 2- D. Ag+, Cr 3+^ , and O 2-
- A 1200 mL sample of helium gas is at a pressure of 350 mmHg and a temperature of 300 K. What volume will this gas sample occupy if the pressure is increased to 700 mmHg and the temperature is increased to 400 K?
A. 450 mL B. 800 mL C. 1650 mL D. 3200 mL
- Compressing a fixed quantity of gas while keeping its temperature constant produces a higher pressure, because:
A. There are more molecules per unit volume after compression. B. There are fewer molecules per unit volume after compression. C. The elasticity of the molecules increases. D. The molecules move faster. E. Each molecule hits the container wall harder.
- Which gas, present in the same closed system, has the greatest average kinetic energy at a given temperature?
A. Hydrogen B. Neon C. Carbon dioxide D. None, the average kinetic energy is the same for each gas.
- The ammonium ion is symmetrical, with nitrogen at the center of a tetrahedron of four equivalent hydrogens. The bonding in the ion may best be described in terms of
A. sp 3 hybridization for the nitrogen. B. sp 2 hybridization for the nitrogen. C. pure p bonding for the nitrogen. D. pure s bonding for the nitrogen.
- Which of these molecules is the most polar? (X and Y are two different elements, Y being the more electronegative).
A. X 2 C. X^ Y^ X
B.
X
Y X D.
Y
X
X
X
E. Y 2
- Which geometry is associated with an sp hybridized atom?
A. Pyramidal B. Tetrahedral C. Triagonal planar D. Linear
- In which group can each substance act as an oxidizing agent?
A. Cl2, MnO2, Cu B. Cl 2 , MnO 4 -1^ , Cu2+ C. Cl-^ , MnO 4 -1, Cu+ D. Cl 2 , Mn, Cu2+
- An oxidizing agent, when involved in a redox reaction,
A. Is always reduced. B. Always contains oxygen. C. Always gives off electrons. D. Is always a metal. E. is called a catalyst
- Oxidation and reduction occur in this chemical reaction. The coefficients are represented by the symbols a...e. a P + b HNO 3 + c H 2 O → d NO + e H 3 PO 4
The increase in oxidation number of the atom oxidized is: A. 1 B 2 C. 3 D. 4 E. 5
- Which element has the smallest atomic radius?
A. Fluorine B. Chlorine C. Bromine D. Iodine E. Astatine
