1) Which one of the following is the formula of hydrochloric acid?
A) HClO3
B) HClO4
C) HClO
D) HCl
E) HClO2
2) Sulfur dioxide is not released into the atmosphere in any significant amount by
________.
A) burning of coal
B) bacterial action
C) internal combustion engines
D) volcanic eruption
E) Sulfur dioxide is produced in significant amount by all of these processes.
3) In the nuclear transmutation, O (p, ) N, what is the bombarding particle?
A) an alpha particle
B) a beta particle
C) a gamma photon
D) a proton
E) a phosphorus nucleus
4) Which one of the following statements regarding Kw is false?
A) pKw is 14.00 at 25 oC.
B) The value of Kw is always 1.0 x 10-14.
C) Kw changes with temperature.
D) The value of Kw shows that water is a weak acid.
E) Kw is known as the ion product of water.
5) The specific heat capacity of liquid water is 4.18 J/g-K. How many joules of heat are
needed to raise the temperature of 7.25 g of water from 20.0 °C to 44.1 °C?
A) 41.8 J
B) 730 J
C) 1.94 x 103 J
D) 2.39 x 10-2 J
E) 66.8 J
6) Silver has two naturally occurring isotopes with the following isotopic masses:
Ar Ar
106.90509108.9047
The average atomic mass of silver is 107.8682 amu. The fractional abundance of the
lighter of the two isotopes is ________.
A) 0.24221
B) 0.48168
C) 0.51835
D) 0.75783
E) 0.90474
7) The basis of the VSEPR model of molecular bonding is ________.
A) regions of electron density on an atom will organize themselves so as to maximize
s-character
B) regions of electron density in the valence shell of an atom will arrange themselves so
as to maximize overlap
C) atomic orbitals of the bonding atoms must overlap for a bond to form
D) electron domains in the valence shell of an atom will arrange themselves so as to
minimize repulsions
E) hybrid orbitals will form as necessary to, as closely as possible, achieve spherical
symmetry
8) Isotopes are atoms that have the same ________ but differing ________.
A) atomic masses, charges
B) mass numbers, atomic numbers
C) atomic numbers, mass numbers
D) charges, atomic masses
E) mass numbers, charges
9) There are ________ oxygen atoms in 30 molecules of C20H42S3O2.
A) 6.0 x 1023
B) 1.8 x 1025
C) 3.6 x 1025
D) 1.2 x 1024
E) 60
10) A solution is prepared by dissolving 11.0 g of NH3 in 250.0 g of water. The density
of the resulting solution is 0.974 g/mL. The mole fraction of NH3 in the solution is
________.
A) 0.0440
B) 0.0445
C) 0.940
D) 0.922
E) 16.8
11) Carbon-11 is used in medical imaging. The half-life of this radioisotope is 20.4 min.
What percentage of a sample remains after 50.0 min?
A) 66.5
B) 8.62
C) 18.3
D) 40.8
E) 2.45
12) In comparing the same two atoms bonded together, the ________ the bond order,
the ________ the bond length, and the ________ the bond energy.
A) greater, shorter, greater
B) greater, greater, greater
C) greater, longer, greater
D) smaller, longer, smaller
E) smaller, greater, greater
13) Automobile air bags use the decomposition of sodium azide as their source of gas
for rapid inflation:
2NaN3 (s) → 2Na (s) + 3N2 (g).
What mass (g) of NaN3 is required to provide 26.5 L of N2 at 22.0 °C and 1.10 atm?
A) 52.2
B) 700.
C) 0.807
D) 1.21
E) 1.10