Final Exam Review #2
Supplemental Instruction
Iowa State University
Leader:
Course:
Instructor:
Date:
Allison
Chem 163
Dr. Appy
12/10/14
1. For each of the following compounds, indicate ALL of the types of intermolecular
forces that each would experience (London Forces, Dipole Interaction, Hydrogen
Bonding).
a. H2 O
London, Dipole, and Hydrogen
b. CH4
London
c. PCl3
Dipole
d. NH3
Hydrogen, Dipole, London
e. C2 H6
London
2. Put the following intermolecular forces in order of strongest to weakest: IonDipole, London Forces, Dipole-Dipole, Hydrogen Bonds
Ion-Dipole, Hydrogen Bonds, Dipole-Dipole, London Dispersion
3. Put the following in order of the highest boiling point to the lowest boiling point:
Ammonia, Phosphorus trichloride, Carbon dioxide
Ammonia, Phosphorus trichloride, Carbon dioxide
Strongest to Weakest bonds
4. Balance the following equations:
a. 1Na2 O2 + 1H2 O ➔2NaOH + 2O2
b. 1Ca3(PO4) 2 + 8C ➔1Ca3P2 + 8CO
c. 2 S + 3O2 ➔2SO3
d. 2CO + 1O2 ➔2CO2
e. 1C + 1H2O ➔1CO + 1H2
f. 1NH4NO3 ➔1N2O + 2H2O
5. For each of the following, predict the products and balance the molecular
equation, then write the complete ionic and net ionic equations.
a. NaCl (aq) + AgNO3 (aq) ---> NaNO3 (aq) + AgCl (s)
Complete:
net ionic:
Na+(aq) + Cl-(aq) + Ag+(aq) + NO3-(aq)  Na+(aq) +NO3-(aq) + AgCl(s)
Cl-(aq) + Ag+(aq)  AgCl(s)
a. 2 NaCl (aq) + Pb(NO3) 2 (aq) ---> 2 NaNO3 (aq) + PbCl2 (s)
Complete: 2 Na+(aq) + 2Cl-(aq) + Pb2+(aq) + 2NO3-(aq)  2Na+(aq) + 2NO3-(aq) + PbCl2 (s)
Net ionic:
Pb2+(aq) + 2Cl-(aq)  PbCl2 (s)
b. H2SO4 (aq) + Ba(OH) 2 (aq) ---> 2 H2O (l) + BaSO4 (s)
Complete: 2 H+(aq) + 2SO4- + Ba2+(aq) + 2 OH-(aq) ---> 2 H2O (l) + BaSO4 (s)
Net ionic: SAME ^
6. Use the equation below to answer the following questions
Pb + O2 ---> PbO2
a. If 3.45 g of Pb reacts with an excess of O2, what is the maximum
amount of PbO2 (in grams) that can be produced?
3.98 g PbO2
b. What is the minimum amount of oxygen (in grams) required to
completely react with 3.45 g of Pb?
0.533 g O2
c. How many Pb molecules are there in 3.45 g of Pb?
1.00 x 10^22 molecules
7. If you react 5.00 g of CH4 with 12.00 g of O2, what is theoretical yield of H20?
CH4 + 2 O2 ---> CO2 + 2 H2O
5.00 g CH4 x (1 mol CH4) x (2 mol H2O) = 0.623 mol H2O
(16.04 g CH4)
(1 mol CH4)
12.00 g O2 x (1 mol O2) x (2 mol H2O) = 0.375 mol H20 <<< Limiting Reactant
(32.0 g O2)
(2 mol O2)
0.375 mol H2O x (18.02 g H2O) = 6.76 g H20
(1 mol H2O)
8. Consider the following unbalanced equation:
4P + 5O2 ---> 2P2O5
a. How many grams of phosphorus are required to react completely with
20.0 g of O2?
20.0 g O2 x (1 mol O2) x (4 mol P) x (31.0 g P)
(32.0 g O2)
(5 mol O2)
= 15.5 g P
(1 mol P)
b. What is the theoretical yield in grams if you combine the amounts of
the reactants in part a?
15.5 g P x (1 mol P) x (2 mol P2O5) = 0.250 mol P2O5
(31.0 g P)
(4 mol P)
20.0 g O2 x (1 mol O2) x (2 mol P2O5) = 0.250 mol P2O5
(32.0 g O2)
(5 mol O2)
0.250 mol P2O5 x (142.0 g P2O5) = 35.5 g P2O5
(1 mol P2O5)
9. Assign oxidation numbers to each element in the following compounds or
polyatomic ions
a. MgBr2
Mg: 2+, Br: 1b. Fe2O3
Fe: 3+, O: 2-
c. SO3 2-
S: 4+, O: 2-
d. PO4 3-
P: 5+, O: 2-
e. HClO2
H: 1+, Cl: 3+, O:2+
f. CuSO4
Cu: 2+, S: 6+, O: 2-
10. Define:
a. Reduction: a gain of electrons
i. Oxidation number goes from a higher to lower value
b. Oxidation: A loss of electrons
i. Oxidation number goes from a lower to a higher value
11. Identify the species being oxidized and reduced in each of the following
reactions
a. 2 Cr+ + Sn4+ ----> Cr3+ + Sn2+
i. Cr is oxidized, Sn is reduced
b. 3 Hg2+ + 2 Fe ----> 3 Hg2 + Fe 3+
i. Fe is oxidized, Hg is reduced
c. 2 As + 3 Cl2 ----> 2 AsCl3
i. As is oxidized, Cl is reduced
d. 2 NaBr + Cl2 ----> NaCl + Br2
i. Br is oxidized, Cl is reduced
12. Construct a battery based on the following equation. Include and label all
necessary components. Also indicate which electrode is the anode/cathode,
at which electrode reduction/oxidation is taking place, and the direction of
electron flow.
Zn(s) + NiCl2(aq) ---> ZnCl2(aq) + Ni(s)
13. If you have 4.0 moles of a gas at a pressure of 7.8 atm and volume of 16.0
liters, what is the temperature?
T = (7.8 atm) x (16.0 L) = 380 degrees Celsius
(4.0 mol) x ( 0.0821)
14. If I initially have a gas with a pressure of 9.7 atm and temperature of 45.0 0C
and I heat it up to 107.5 0C, what will the new pressure be? Assume the
volume in the container is constant.
Pf = (9.7 atm) x (107.5) = 23 atm
(45.0)
15. How many mL of a 6.0 M solution of NaCl do you need to obtain 150.0 g of
NaCl?
150.0 g NaCl x 1 mol NaCl = 2.56 mol NaCl x
58.5 g NaCl
1L
= 0.427 L
6.0 mol
0.427 L x 1000 mL = 427 mL
16. A solution is prepared by mixing 55.0 g of NaCl with enough water to make
300.0 mL of solution. What is the molarity of the solution?
50.0 g NaCl x 1 mol NaCl
58.5 g NaCl
= 0.940 mol
(0.3000L)
=3.13 M
17. How many mL of the solution in Question 16 are needed to provide 45.0
grams of NaCl?
45.0 g NaCl x 1 mol
58.5 g NaCl
=
0.769 mol
= 0.246 L
3.13 M
0.246 L x 1000mL = 246 mL
18. Describe how you would prepare a 350.0 mL of a 0.900 M solution of NaCl
from solid NaCl and water.
350.0 mL/1000 mL = .3500 L x 0.900 mol = 0.315 mol
1L
0.315 mol x 58.5 g NaCl
1 mol
= 18.4 g NaCl is needed to mix with 350.0 mL to
create a 0.9000 M solution of NaCl
Useful Equations and Constants:
1 mole = 6.022 x 1023 things
PV = nRT
PiVi/(niTi) = PfVf/(nfTf)
MM = mRT/(PV)
MiVi = MfVf
R = 0.0821 L*atm/(mol*K)
STP = 0 °C and 1 atm
K = °C + 273.15
ΔTf,b = Kf,b x moles of solute / (Kg solvent)
P = F/A