1) Predict the empirical formula of the ionic compound that forms from magnesium and
oxygen.
A) Mg2O
B) MgO
C) MgO2
D) Mg2O2
E) Mg3O2
2) What is the maximum number of double bonds that a hydrogen atom can form?
A) 0
B) 1
C) 2
D) 3
E) 4
3) What are the respective concentrations (M) of Mg2+ and C2H3O2
– afforded by
dissolving 0.600 mol Mg(C2H3O2)2 in water and diluting to 135 mL?
A) 0.444 and 0.889
B) 0.0444 and 0.0889
C) 0..889 and 0.444
D) 0.444 and 0.444
E) 4.44 and 8.89
4) A rock contains 0.153 mg of lead-206 for each milligram of uranium-238. The
half-life for the decay of uranium-238 to lead-206 is 4.5 x 109 yr. The rock was formed
________ years ago.
A) 6.89 x 108
B) 5.60 x 108
C) 7.33 x 108
D) 1.06 x 109
E) 8.08 x 108
5) Calculate the mole fraction of nitric acid of a 18.6% (by mass) aqueous solution of
nitric acid.
A) 0.0484
B) 0.0508
C) 0.0967
D) 0.0242
E) The density of the solution is needed to solve the problem.
6) The addition of HBr to 2-butene produces ________.
A) 1-bromobutane
B) 2-bromobutane
C) 1,2-dibromobutane
D) 2,3-dibromobutane
E) no reaction
7) The most common and stable allotrope of sulfur is ________.
A) S
B) S2
C) S4
D) S8
E) Sulfur does not form allotropes.
8) The suffix used for organic molecules containing the ketone functional group is
________.
A) -one
B) -oic acid
C) -oate
D) -amide
E) -ene
9) In the reaction below, ΔH°f is zero for ________.
Ni (s) + 2CO (g) + 2PF3 (g) → Ni(CO)2(PF3)2 (l)
A) Ni (s)
B) CO (g)
C) F3 (g)
D) Ni(CO)2(PF3)2 (l)
E) both CO (g) and PF3 (g)
10) What is the empirical formula of a compound that contains 49.4% K, 20.3% S, and
30.3% O by mass?
A) KSO2
B) KSO3
C) K2SO4
D) K2SO3
E) KSO4
11) “Absolute zero” refers to ________.
A) 0 Kelvin
B) 0° Fahrenheit
C) 0° Celsius
D) °C + 9/5(°F – 32)
E) 273.15 °C
12) The nitride ion is a strong Brnsted-Lowry base. Mg3N2 reacts with water to produce
________.
A) N2
B) N2O
C) NO
D) NO2
E) NH3