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Final Exam Review
Supplemental Instruction
Iowa State University
Leader:
Course:
Instructor:
Date:
Emily
Chem 177
Appy
5/4/15
1. Write the molecular formula for each of the following compounds.
a. sodium sulfate
b. hydrofluoric acid
c. ethanol
d. disulfur dichloride
e. nitric acid
f. butane
g. calcium hydroxide
h. iron (III) nitrate
i. 2-hexene
j. triphosphorus dioxide
k. sulfurous acid
2. Name each of the following compounds.
a. CH4
b. Ca(OH)2
c. H2S
d. Ca3N2
e. C8H18
f. Br2O5
g. HClO4
h. CuSO4
i. CH3Cl
j. FeO
k. HNO2
3. Determine how many grams of PCl3 are produced when 2.80 g of Cl2 reacts with a
sufficient quantity of P4?
4. Copper reacts with sulfuric acid according to the following equation:
2H2SO4 + Cu  CuSO4 + 2H2O + SO2
How many grams of sulfur dioxide are created by this reaction if 14.2 g of copper react
with 18.0 g sulfuric acid?
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5. If 21 g of H2S is mixed with 38 g of O2 and 31 g of SO2 form, what is the percentage
yield?
6. When barium nitrate and sodium phosphate are mixed together in water a precipitate is
formed. What is the most likely chemical formula of the precipitate?
7. Balance the following equation. Then write the total ionic equation and net ionic
equation.
a. (NH4)2S(aq) + FeCl3(aq)  NH4Cl(aq) + Fe2S3(s)
8. Assign oxidation states to each element in the following compounds.
a. SO3
b. PO4 3c. Cr2O7 2d. HClO2
9. Use the changes in oxidation numbers to determine which elements are oxidized and
which are reduced in these reactions. (Note: it is not necessary to use balanced equations)
a. C + H2SO4  CO2 + SO2 + H2O
b. HNO3 + HI  NO + I2 + H2O
c. KMnO4 + HCl  MnCl2 + Cl2 + H2O + KCl
d. Sb + HNO3  Sb2O3 + NO + H2O
10. Use the activity series to predict which reactions will occur.
a. Hg(l) + MnSO4(aq)  HgSO4(s) + Mn(s)
b. 2 Ag (s) + H2SO4(aq)  Ag2SO4(aq) + H2(g)
c. Ca(s) + 2 H2O(l)  Ca(OH)2(aq) + H2(g)
11. Titration reveals that 11.6 mL of 3.0 M sulfuric acid are required to neutralize the
sodium hydroxide in 25.00 mL of NaOH solution. What is the molarity of the NaOH
solution?
12. Small quantities of hydrogen gas can be prepared by the following reaction:
Zn(s) + H2SO4(aq)  ZnSO4(aq) + H2(g)
How many grams of H2 can be prepared from 25.0 mL of 6.00 M H2SO4 and excess zinc?
13. Using these reactions, find the standard enthalpy change for the formation of 1 mol
PbO(s) from lead metal and oxygen gas.
PbO(s) + C(graphite)  Pb(s) + CO(g)
ΔHo = 106.8 kJ
2 C(graphite) + O2(g)  2 CO(g)
ΔHo = -221.0 kJ
If 250.0 g of lead reacts with oxygen to from lead (II) oxide, what quantity of thermal
energy (in kJ) is absorbed or evolved?
14. Given the thermochemical equation:
N2(g) + O2(g) → 2 NO(g)
ΔH = 180.6 kJ
If 558 kJ of energy are supplied, what mass of NO can be made?
15. A piece of titanium metal with a mass of 20.8 g is heated in boiling water to 99.5°C and
then dropped into a coffee cup calorimeter containing 75.0 g of water at 21.7°C. When
thermal equilibrium is reached, the final temperature is 24.3°C. Calculate the specific
heat capacity of titanium. (The specific heat of water is 4.18 J/g°C.)
16. A 1.000 g sample of octane (C8H18) is burned in a bomb calorimeter containing 1200
grams of water at an initial temperature of 25.00ºC. After the reaction, the final
temperature of the water is 33.20ºC. The heat capacity of the calorimeter is 837 J/ºC. The
specific heat of water is 4.184 J/g ºC. Calculate the heat of combustion of octane in
kJ/mol.
17. Write a formation reaction for ethyl alcohol, C2H5OH(l).
18. Calculate the heat of combustion of diborane (B2H6):
B2H6(g)
H2O(g)
B2O3(s)
ΔH°f
36.0 kJ/mol
-241.8 kJ/mol
-1273.4 kJ/mol
19. 0.20 moles of HCl were neutralized by NaOH. The concentrations of the base and acid
were equal. If the temperature of the water in the calorimeter increased from 19.9 to 24.6
C, what was the original concentration of HCl?
(Molar heat of neutralization = -80 kJ/mol of HCl)
20. Complete the following table.
Element
Atomic
Number
Ground State # Of core
Electronic
electrons
Configuration
Z effective
# Unpaired
Electrons
Si
Cl
Ca
21. Use the concept of Z effective to discuss the atomic size difference between Si and Cl.
22. Write chemical reactions to describe the reaction between:
a. Na(s) and H2(g)
b. Ca(s) and HCl(g)
c. Al2O3(s) and HCl(aq)
d. H2(g) and Cl2(g)
e. Ba(s) and Br2(l)
f. Li(s) and H2O(l)
23. Which ionic crystal should have the largest lattice energy?
a. LiCl
b. LiBr
c. CaO
d. SrO
e. BaSO4
24. The complete combustion of propane can be represented by the following equation:
CH3CH2CH3(g) + 5 O2(g)  3 CO2(g) + 4 H2O(l)
Find the ΔH for the reactions given the following bond enthalpies.
C-H
C-C
O=O
C=O
H-O
413 kJ/mol
347 kJ/mol
498 kJ/mol
805 kJ/mol
464 kJ/mol
25. Which molecule does not have a dipole moment?
a. CO
b. HBr
c. CH3Cl
d. XeF4
e. NH3
26. How many liters of O2(g) at STP are evolved when 3.25 g of KNO3(s) decomposed to
KNO2(s) and O2(g)?
27. During a collision, automobile air bags are inflated by the N2 gas formed by the explosive
decomposition of sodium azide, NaN3:
2 NaN3  2 Na + 3 N2
What mass of sodium azide would be needed to inflate a 30.0 L bag to a pressure of 1.40
atm at 25°C?
28. The mean molar mass of the atmosphere at the surface of Titan is, Saturn’s larges moon,
is 28.6 g/mol. The surface temperature is 95 K, and the pressure is 1.6 atm. Assuming
ideal behavior, calculate the density of Titan’s atmosphere.
29. A 0.50 mol sample of oxygen is confined at 0°C and 1 atm in a cylinder with a movable
piston. The piston compresses the gas so that the final volume is half the initial volume
and the final pressure is 2.2 atm. What is the final temperature of the gas in degree
Celsius?
30. Rank the following compounds from lowest to highest boiling point: calcium
carbonate, methane, methanol (CH4O), dimethyl ether (CH3OCH3).
31. Which molecule will have the higher vapor pressure between CO2 and SO2?
32. What are the bond orders for N2, N2+, and N2-? Which one of the three species is the most
stable?
33. Suppose a barometer is constructed using methanol as the liquid. Given that the density
of Hg is 13.6 g/mL and that of methanol is 0.791 g/mL, and disregarding the effect of
methanol gas molecules above methanol liquid, calculate the height of the methanol
column at 1 atm of pressure and 0°C. Why do we use Hg rather than methanol as a liquid
in a barometer?
34. What is the heat in Joules required to convert 25 grams of -10 °C ice into 150 °C steam?
The heat of fusion of water is 334 J/g, heat of vaporization of water is 2257 J/g, the
specific heat of ice is 2.09 J/g°C, the specific heat of water is 4.18 J/g°C, and the specific
heat of steam is 2.09 J/g°C.
35. What is the root mean square velocity of a molecule in a sample of oxygen at 0°C?