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CHM 134 General Chemistry I
Exam 1, Fall 2014 – Dr. Foresman
Name
1. (11 points) Provide the lowest, whole-number coefficients needed to properly
balance each equation. A blank will be assumed to be a coefficient of 1.
———
———
HCl(aq)
C6H14(l)
+
+
———
Fe2O3(s)
→
———
H2O(l)
+
———
FeCl3(s)
———
H2O2(aq)
→
———
H2O(l)
+
———
O2(g)
———
O2(g)
→
———
CO2(g)
+
———
H2O(l)
2. (4 points) Complete and balance these gas forming reactions, include (aq) and (g):
KHCO3 (s) + HNO3 (aq) 
Ca(OH)2 (s) + NH4Br (aq) 
3. (6 points) What is the oxidation state of the element indicated in each case?
As in H3AsO4
Ni in NiO2
Cr in CrCl3
P in P4
C in CH2O
S in H2SO4
4. (10 points) According to the following reaction, how many grams of hydrochloric
acid (HCl) are produced from the complete reaction of 15.7 grams of Cl2 gas?
3 Cl2(g) + 3 H2O(l)
5 HCl(aq) + HClO3(aq)
5. (10 points) For the following reaction, 30.8 grams of carbon disulfide are allowed to
react with 98.4 grams of chlorine gas.
CS2(s) + 4 Cl2(g)
CCl4(l) + 2 SCl2(s)
What is the maximum mass of carbon tetrachloride that can be formed?
6. (6 points) In the redox reaction below, use oxidation numbers to identify the element
oxidized, the element reduced, and the number of electrons transferred in the redox
process.
3 Cu + 2 HNO3 + 6 H+
2 NO + 3 Cu2+ + 4 H2O
7. (6 points) In the redox reaction below, use oxidation numbers to identify the
oxidizing agent, the reducing agent, and the number of electrons transferred in the
redox process.
3 ClO2 + NO3- + H2O
NO + 3 ClO3- + 2 H+
8. (12 points) Write the products for each of these reactions. You must include the state
of matter and balance the overall equation.
K2SO3(aq) +
NaOH(aq) +
HBr(aq) →
HNO3(aq)
→
CuSO4(aq) + AgNO3(aq) →
NaI(aq) + Pb(NO3)2(aq) →
LiOH(aq)
+ H2SO4(aq) →
(NH4)2SO4(aq) + Ca(NO3)2(aq) →
9. (9 points) If 6.67 grams of CuCl2 are mixed with excess AgNO3. The reaction yields
9.83 grams of AgCl. What is the percent yield of silver chloride?
2 AgNO3(aq) + CuCl2(s)
2 AgCl(s) + Cu(NO3)2(aq)
10. (8 points) In the laboratory you dissolve 19.8 g of zinc sulfate in a volumetric flask
and add water to a total volume of 125 mL. What is the molarity of the solution?
11. (8 points) What volume of a 0.100 M NaOH solution is required to neutralize 25.0
mL of a 0.400 M H2SO4 solution?
2 NaOH(aq) + H2SO4(aq) Na2SO4(aq) + 2H2O(l)
12. (10 points) Potassium hydrogen phthalate (KC8H5O4) is a solid, monoprotic acid
frequently used in the laboratory to standardize strong base solutions. How many
grams of KC8H5O4 are needed to exactly neutralize 35.0 mL of a 0.482 M potassium
hydroxide solution?