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Accelerated Chemistry Exam Review Problems
Answer Section
MULTIPLE CHOICE
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E
PTS: 1
OBJ: 03-10 Determining Empirical and Molecular Formulas
C
PTS: 1
OBJ: 04-5 Reactions with One Reactant in Limited Supply
C
PTS: 1
OBJ: 04-6 Evaluation the Success of a Synthesis: Percent Yield
D
PTS: 1
OBJ: 10.5 The Ideal Gas Law
C
PTS: 1
OBJ: 10.6 The Quantities of Gases in Chemical Reactions
D
PTS: 1
OBJ: 10.6 The Quantities of Gases in Chemical Reactions
C
PTS: 1
OBJ: 10.6 The Quantities of Gases in Chemical Reactions
E
PTS: 1
OBJ: 10.7 Gas Density and Molar Masses
D
PTS: 1
OBJ: 10.8 Gas Mixtures and Partial Pressures
D
PTS: 1
OBJ: 10.8 Gas Mixtures and Partial Pressures
E
PTS: 1
OBJ: 13.3 Rate Law and Order of Reaction
A
PTS: 1
OBJ: 13.3 Rate Law and Order of Reaction
A
PTS: 1
OBJ: 13.7 Reaction Mechanisms
C
PTS: 1
OBJ: 13.7 Reaction Mechanisms
C
PTS: 1
OBJ: 13.7 Reaction Mechanisms
B
PTS: 1
OBJ: 14.3 Determining Equilibrium Constants
E
PTS: 1
OBJ: 19.1 Redox Reactions
B
PTS: 1
05-1 Exchange Reactions: Precipitation and Net Ionic Equations
A
PTS: 1
OBJ: 05-3 Oxidation-Reduction Reactions
D
PTS: 1
05-5 Displacement Reactions | Redox | and the Activity Series
C
PTS: 1
OBJ: 05-6 Solution Concentration
E
PTS: 1
OBJ: 05-8 Aqueous Solution Titrations
A
PTS: 1
OBJ: 05-8 Aqueous Solution Titrations
SHORT ANSWER
24. ANS:
silicon
PTS: 1
25. ANS:
PTS: 1
26. ANS:
The solution is unsaturated. Concentration = 33 mg solute / 475 mL solution = 6.9 mg/100mL, which is less than
the solubility, 7.3 mg/100 mL.
PTS: 1
27. ANS:
The oxidation process is clearly
Zn(s)  Zn2+(aq) + 2eThe reduction can be balanced as follows:
NO3-  NO + 2 H2O
NO3- + 4 H+  NO + 2 H2O
NO3- + 4 H+ + 3 e-  NO + 2 H2O
(balance O atoms using H2O)
(balance H atoms using H+)
(balance charge using e-)
Now multiply oxidation process by 3, reduction by 2, so that e- cancel, and add:
3 Zn(s) + 2 NO3-(aq) + 8 H+(aq)  3 Zn2+(aq) + 2 NO(g) + 4 H2O (l)
2....7....5...2...1...1..
PTS: 1
28. Write the complete balanced equation for the reaction between:
a. sulfuric acid and aluminum sulfide.
3H2SO4(aq)
+
Al2S3(s)

3H2S(g)
+ Al2(SO4)3
b. iodine and potassium chloride
I2(s)
+
KCl(aq)  NR
c. ammonium carbonate and chromic acid
(NH4)2CO3(aq)
+
H2CrO4(aq)

(NH4)2CrO4(aq)
+
CO2(g)
+ H2O(l)
29. Calculate the molarity, molality and mole fraction of ammonia for a solution of 30.0g of ammonia in 70.0 g of
water. The density of the solution is 0.982 g/ml.
Molarity= 1.76mol/.1018 L = 17.3M
(total mass = 100.0 g of solution x .982 g/ml = 101.8 ml of solution)
Molality= 1.76 mol/.0700 kg = 25.1 m
XNH3 = 1.76mol/(1.76mol+3.89mol) = 0.312
30. What is the solubility of sodium nitrate in 250 ml of water at 55 oC?
Find solubility of sodium nitrate per 100g of water and set up a proportion to solve for the amount out of
250g