1) The Henry’s law constant for helium gas in water at 30 oC is 3.70 x 10-4 M/atm.
When the partial pressure of helium above a sample of water is 0.400 atm, the
concentration of helium in the water is ________ M.
A) 9.25 x 10-4
B) 1.08 x 103
C) 0.800
D) 1.48 x 10-4
E) 3.70 x 10-4
2) If we start with 1.000 g of cobalt-60, 0.400 g will remain after 7.00 yr. This means
that the half-life of cobalt-60 is ________ yr.
A) 12.1
B) 17.5
C) 2.80
D) 5.30
E) 7.65
3) Of the following, the most nonmetallic element is ________.
A) Cl
B) S
C) P
D) Br
E) Se
4) The internal energy of a system is always increased by ________.
A) adding heat to the system
B) having the system do work on the surroundings
C) withdrawing heat from the system
D) adding heat to the system and having the system do work on the surroundings
E) a volume compression
5) How many grams of NaOH (MW = 40.0) are there in 200.0 mL of a 0.175 M NaOH
solution?
A) .00219
B) 114
C) 1.40
D) 0.0350
E) 14.0
6) The missing product from this reaction is ________.
Al + n –> Si + _____
A) He
B) e
C) n
D) e
E)
7) The ________ have the most negative electron affinities.
A) alkaline earth metals
B) alkali metals
C) halogens
D) transition metals
E) chalcogens
8) The oxidation state of fluorine in its compounds is ________.
A) positive unless it combines with another halogen
B) negative unless it combines with another halogen
C) negative unless it combines with oxygen
D) negative unless it combines with an active metal
E) always negative
9) Of the following gases, ________ will have the greatest rate of effusion at a given
temperature.
A) NH3
B) CH4
C) Ar
D) HBr
E) HCl
10) The beta decay of cesium-137 has a half-life of 30.0 years. How many years must
pass to reduce a 25 mg sample of cesium 137 to 8.7 mg?
A) 46
B) 32
C) 3.2
D) 50
E) 52
11) Magnesium burns in air with a dazzling brilliance to produce magnesium oxide:
2Mg (s) + O2 (g) → 2MgO (s)
How many moles of O2 are consumed when 3.55 mol of magnesium burns?
A) 0.146
B) 0.563
C) 3.55
D) 7.10
E) 1.78
12) Which of the following equations correctly represents the reaction of B2H6 with
oxygen?
A) B2H6 (g) + 3O2 (g) –> B2O3 (s) + 3H2O (g)
B) B2H6 (g) + O2 (g) –> B2O2 (s) + 3H2 (g)
C) B2H6 (g) + 2O2 (g) –> B2H2 (s) + 2H2O2 (aq)
D) B2H6 (g) + 2O2 (g) –> B2O2 (s) + 3H2 + O2 (g)
E) B2H6 (g) + O2 (g) –> H2B2O2 (s) + 2H2 (g)
13) The rate law for this reaction is rate = ________.
A) k[A][B]
B) k[P]
C) k[A]2[B]
D) k[A]2[B]2
E) k[A]2
14) The standard Gibbs free energy of formation of ________ is zero.
(a) Mn (s)
(b) I2 (s)
(c) Cu (s)
A) (a) only
B) (b) only
C) (c) only
D) (b) and (c)
E) (a), (b), and (c)
15) Of the following acids, ________ is not a strong acid.
A) HNO2
B) H2SO4
C) HNO3
D) HClO4
E) HCl
16) The overall order of the reaction is ________.
A) 1
B) 2
C) 3
D) 4
E) 0
17) Which below best describe(s) the behavior of an amphoteric hydroxide in water?
A) With conc. aq. NaOH, its suspension dissolves.
B) With conc. aq. HCl, its suspension dissolves.
C) With conc. aq. NaOH, its clear solution forms a precipitate.
D) With conc. aq. HCl, its clear solution forms a precipitate.
E) With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves.
18) How many electrons are there in one atom of 71Ga?
A) 40
B) 70
C) 71
D) 31
E) 13
19) Addition of B2O3 to soda-lime glass ________.
A) imparts a greater ability to withstand temperature change
B) imparts a deep blue color
C) results in a denser glass with a higher refractive index
D) results in a glass with a lower melting point
E) results in opaque glass