1. What is the oxidation number of S in
sulfur dioxide gas, SO2?
2. What is the oxidation number of S in
the persulfate ion, S2O8-2 ?
3. For the reaction:
8H+ + MnO4- + 5Fe+2 --> Mn+2 +5Fe+3 + 4H2O
Which substance is acting as a reducing agent?
4. Which of the following are redox
reactions?
a. Mg + 2HCl --> MgCl2 + H2
b. NO2 + H2O --> HNO3
c. H3PO4 + 3NaOH --> Na3PO4 + 3H2O
d. 3AgNO3 + Na3PO4 --> Ag3PO4 + 3NaNO3
e. two of the above
f. three of the above
5. A common surface treatment for
aluminum involves the intentional
surface oxidation in an electrolytic cell:
Al(s) + O2(g) --> Al2O3(s)
This is also known as:
a. Plating
b. Galvanizing
c. Cathodic Protection
d. Anodization/Passivation
e. Enameling
6. What current, in amperes, is required to
produce 1.00 lb of aluminum per minute in
an industrial cell? (1 F = 96,485 C/mole e-,
1 Amp = 1 C/sec, MWt. of Al = 26.98 g/mol,
Al+3 + 3e- --> Al, 1.00 lb = 454 gm)
7. From the following half cell data, determine
the Ksp of PbSO4 . The Ksp expression is:
PbSO4(s) --> Pb+2(aq) + SO4-2(aq)
PbSO4(s) + 2e- --> Pb(s) + SO4-2(aq) Eo = -0.35 V
Pb+2(aq) + 2e- --> Pb(s) ( Eo = -0.13 V
Starting with Pb (lead) and Al (aluminum) metal strips and 1.0 M solutions of Pb(NO3)2 and Al(NO3)3, you are to construct a battery based on the following half cell data:
Eo
Pb+2 + 2e- ---> Pb -0.13 V
Al+3 + 3e- ---> Al -1.66 V
8. Label the Cathode and Anode in the drawing above, based on the given direction of electron flow.
9. Write the overall balanced spontaneous cell reaction:
10. What is the standard cell voltage?
(1.00 M ion concentrations:)
11. Cathode (metal):
12. Cathode reaction:
13. Anode (metal):
14. Anode reaction:
15. Which electrode will gain mass as the cell reaction proceeds? (Show reaction)
16. Show the direction of ion flow through the salt bridge in the drawing above if it is filled with KNO3 solution.
(K+ and NO3- ions)
17. What is the cell voltage when the reaction reaches equilibrium?
18. What is the equilibrium constant for this reaction? (F = 96,485 C/mole e-)
19. If [Al+3] = 0.010 M and [Pb+2] = 1.00 M, calculate the Ecell
20. The main function of the salt bridge in a battery is:
a. to serve as a site for oxidation and reduction reactions
b. to provide a path for electron transfer
c. to provide a path for ion transfer
d. two of the above
e. all of the above
f. none of the above
21. A standard UV source is a mercury arc
lamp, which emits primarily at 254 nm.
What is the frequency of this radiation?
(1 nm = 10-9 m, c = 3.00 x 108 m/sec)
22. What is the energy of a single photon of
the above 254 nm light?
(h = 6.63 x 10-34 J sec)
23. Lithium metal requires 279.7 kJ/mole to
remove an electron. Find the maximum
wavelength of light that can do this.
(N = 6.022 x 1023 atoms/mole, 1 kJ = 103 J.)
24. If the 254 nm radiation from the UV
source above falls on lithium metal, what
is the maximum kinetic energy of the
ejected electrons?
25. What is the wavelength of light
corresponding to a transition from
n=1 to n=2 for hydrogen?
26. Calculate the velocity of an electron with a
deBroglie wavelength of 1.0 Angstrom.
(1 Angstrom = 10-10 m, h = 6.63 x 10-34 J sec)
27. The quantum number which describes the different spatial orientations of
degenerate orbitals is
a. principal
b. angular
c. magnetic
d. spin
e. none is correct
28. In going from left to right across a row in
the periodic table, the diameter of atoms
(increases/decreases) due to__________
29. In going down within a column in the
periodic table, the first ionization energy
(increases/decreases) due to __________
30. Write the electron configuration for a neutral nitrogen atom. How many unpaired electrons are present?
31. Write the electron configuration for a
neutral magnesium atom.
32. What type of electron configuration
would be an indication that the atom might show magnetic properties?
33. Label on the periodic table:
Noble Gases, Halogens,
Alkaline Earth Metals, Alkalai Metals,
Rare Earths, Transuranium Elements, Transition Metals
34. Show which orbitals (s, p, d, f) are being filled in the various regions of the periodic table.