1) A Lewis acid is an electron-pair acceptor, and a Lewis base is an electron-pair donor.
2) The larger the principal quantum number of an orbital, the lower is the energy of the
electrons in that orbital.
3) The compound HClO4 is a weak acid.
4) Racemic mixtures of enantiomers do not rotate the plane of polarized light.
5) Calcium carbide is a solid source of acetylene.
6) The partial pressure of a component in a gas mixture is the product of its mole
fraction and the total mixture pressure.
7) The stability of benzene is a major function of delocalized € bonding.
8) An NMR spectrum results from photon irradiation in which the nuclear spin
alignment is flipped.
9) The more negative G o is for a given reaction, the larger the value of the
corresponding equilibrium constant, K.
10) The mass of a single atom of an element (in amu) is numerically equal to the mass
in grams of 1 mole of that element.
11) A scientific theory is a concise statement or an equation that summarizes a broad
variety of observations.
12) The rate of a second order reaction can depend on the concentrations of more than
one reactant.
13) HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol
of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at
25.0 oC. The Ka of HZ is ________.
A) 1.2 x 10-5
B) 6.9 x 10-9
C) 1.4 x 10-10
D) 9.9 x 10-2
E) 2.8 x 10-12
14) The solubility of MnSO4 monohydrate in water at 20 oC is 70.0 g per 100.0 mL of
water. A solution at 20 oC that is 0.401 M in MnSO4 monohydrate is best described as
a(n) ________ solution. The formula weight of MnSO4 monohydrate is 168.97 g/mol.
A) hydrated
B) solvated
C) saturated
D) unsaturated
E) supersaturated
15) A solution with a concentration higher than the solubility is ________.
A) not possible
B) unsaturated
C) supercritical
D) saturated
E) supersaturated
16) The molecular geometry of the SF2 molecule is ________.
A) linear
B) bent
C) trigonal planar
D) tetrahedral
E) octahedral
17) A particular first-order reaction has a rate constant of 1.35 x 102 s-1 at 25.0 oC.
What is the magnitude of k at 65.0 oC if Ea = 55.5 kJ/mol?
A) 1.92 x 103
B) 1.95 x 104
C) 358
D) 3.48 x 1073
E) 1.35 x 102
18) Thermodynamic Quantities for Selected Substances at 298.15 K (25 oC)
The value of S o for the reaction
2C (s, diamond) + O2 (g) –> 2CO (g)
is ________ J/K mol.
A) -185.9
B) +185.9
C) -9.5
D) +9.5
E) -195.7
19) The correct answer (reported to the proper number of significant figures) to the
following is ________.
(2.05631)(6.9391136) / 12.59326 = ________
A) 1.1330639
B) 1.13306
C) 1.133064
D) 1.1361
E) none of the above
20) The oxidation state of chlorine in the ClO– molecule is ________.
A) +1
B) +3
C) +4
D) +5
E) -1
21) There are ________ orbitals in the third shell.
A) 25
B) 4
C) 9
D) 16
E) 1
22) How many grams of H3PO4 are in 145 mL of a 3.50 M solution of H3PO4?
A) 0.508
B) 49.7
C) 20.0
D) 4.90
E) 612
23) 210Pb has a half-life of 22.3 years and decays to produce 206Hg. If you start with
7.52 g of 210Pb, how many grams of 206Hg will you have after 15.8 years?
A) 4.60 g
B) 2.83 g
C) 9.20 g
D) 2.30 g
E) 12.5 g
24) The chelate effect is best attributed to considerations of which type?
A) hydration
B) enthalpy
C) entropy
D) hydrogen bonding
E) resonance
25) If matter is uniform throughout and cannot be separated into other substances by
physical processes, but can be decomposed into other substances by chemical
processes, it is called a(n) ________.
A) heterogeneous mixture
B) element
C) homogeneous mixture
D) compound
E) mixture of elements
26) Calculate the mole fraction of HCl in a 7.20% (by mass) aqueous solution.
A) 0.0369
B) 0.0383
C) 0.0739
D) 0.0185
E) The density of the solution is needed to solve the problem.
27) ________ is isoelectronic with argon.
A) Cl–
B) P4-
C) Ca
D) K–
E) F–
28) The mass number of an atom of 14
C is ________.
A) 6
B) 20
C) 8
D) 14
E) 10
29) What species has the electron configuration [Ar]3d2?
A) Mn2+
B) Cr2+
C) V3+
D) Fe3+
E) K+
30) A solution is prepared by dissolving 23.7 g of CaCl2 in 375 g of water. The density
of the resulting solution is 1.05 g/mL. The mole fraction of Cl– in this solution is
________.
A) 0.0103
B) 0.0200
C) 0.0201
D) 0.0632
E) 0.0630
31) When NaCl dissolves in water, aqueous Na+ and Cl– ions result. The force of
attraction that exists between Na+ and H2O is called a(n) ________ interaction.
A) dipole-dipole
B) ion-ion
C) hydrogen bonding
D) ion-dipole
E) London dispersion force
32) What is the name of the compound below?
33) What is the molecular geometry of a molecule that has three bonding and two
non-bonding domains?
34) Calculate G(in kJ/mol) for the following reaction at 1 atm and 25 oC:
C2H6 (g) + O2 (g) –> CO2 (g) + H2O (l) (unbalanced)
Hf C2H6 (g) = -84.7 kJ/mol; S C2H6 (g) = 229.5 J/K mol;
HfCO2 (g) = -393.5 kJ/mol; S CO2 (g) = 213.6 J/K mol;
Hf H2O (l) = -285.8 kJ/mol; S H2O (l) = 69.9 J/K mol;
S O2 (g) = 205.0 J/K mol
35) If Reaction A + Reaction B = Reaction C, then Kc Reaction C = ________.
36) The most common coordination numbers are ________.
37) The direct conversion of a solid to a gas is called ________.