CH 143 Take Home Exam 2
Electrochemistry, Transition, Nuclear
Students may not seek help on this exam from anyone but April Mixon
TAKE-HOME EXAM STATEMENT OF ACADEMIC HONESTY
(this statement MUST be signed and turned in with the exam in order to receive credit for this exam)
I declare that the answers contained within this exam are mine and mine alone. I agree that
while I may work on this exam with text resources, I may NOT seek help or guidance from any
other person. This includes current students, former students, students in other classes,
scientists, relatives, industry personnel, and anybody else in the universe or beyond (sorry,
Alpha Centauri is out). The only person I may ask questions of is my instructor, April Mixon,
however I understand that she reserves the right to not provide me with answers to my
questions. I understand that the answers that I put down on this exam must be my own, in my
own words, created by me.
I further understand that if I submit answers that are too similar to another person’s in
this class, or are downright plagiarized from any other person or source (printed or electronic),
that I will receive a zero on this exam. I also understand that if I fail to show my work, I will
receive no credit for my answers. This means that if a number is NOT given to me on the exam,
I understand that I need to show where my calculated number came from.
Signed:_____________________________________________________________________
Name: (printed): ____________________________________________________________
SHOW ALL WORK!! NO WORK, NO CREDIT!! SHOW ALL WORK!! NO WORK, NO CREDIT!!
INSERT SPACES OR ANSWER QUESTIONS ON A SEPARATE SHEET OF PAPER!! IF YOU DO
NOT INSERT SPACE OR ANSWER ON A SEPARATE SHEET OF PAPER, I WILL NOT GRADE
THOSE ANSWERS. ALL ANSWERS MUST BE LOCATED IN THE SAME “PLACE”; EITHER
INSERT SPACES IN THE EXAM or ON A SEPARATE PIECE OF PAPER. (exception: the multiple
choice questions maybe be answered on the exam)
The Exam is due, Tuesday, May 25th at 4:00 pm in class.
P.S. Don’t forget your paper is due Thursday, May 27th!
P.P.S. Good Luck!
P.P.P.S. Show all your work – clearly and legibly!
1
CH 143 Take Home Exam 2
Electrochemistry, Transition, Nuclear
Students may not seek help on this exam from anyone but April Mixon
1.) Determine the molar solubility of iron (III) hydroxide (Ksp = 1.6 x 10-39) in a 0.25 M solution of
Fe(NO3)3. (6 pts)
2.) Write the equation for dissolution of the following compound in water and write the solubility
product expression for: (6 pts)
a. Copper (II) sulfide
3.) Write the heat of formation equations with phases for the following compound: (3 pts)
Hf (kJ/mole)
-397.7
Compound
KClO3 (s)
4.) Balance the following redox reaction under acidic AND basic conditions: (10 pts)
S2O3-2 (aq) + MnO4-1 (aq)  SO4-2 (aq) + Mn+2 (aq)
5.) Using the provided table of reduction potentials (class notes or textbook), calculate Eocell for a
voltaic cell consisting of a chromium electrode immersed in a Cr+3 solution and an nickel
electrode immersed in Ni+2 solution. (4 pts)
6.) Combine the following reaction into 3 spontaneous balanced reactions. Calculate Eocell for each
reaction. Rank the relative strengths of the oxidizing and reducing agents. (9 pts)
a. Au+1 (aq) + e-1 → Au (s)
Ered o = + 1.69 V
+2
-1
b. Pb (aq) + 2e → Pb (s)
Ered o = - 0.13 V
c. Cr+3 (aq) + 3 e-1 → Cr (s)
Ered o = - 0.74 V
7.) Consider a voltaic cell which has a copper electrode immersed in a solution of copper (II) sulfate
and a zinc electrode immersed in a solution of zinc sulfate. Determine Eocell. If the concentration
of zinc sulfate is 10 times greater than the concentration of copper sulfate, what is the value of
Ecell at 30.0oC? (8 pts)
8.) A voltaic cell is constructed with a 0.25 M Pb/Pb+2 half-cell and a 0.05 M Pb/Pb+2 half-cell.
Diagram all the components that would make up a working electrochemical cell involving these
species. Label the electrodes as the cathode or anode, make sure to indicate the direction that the
electrons would flow. (5 pts)
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CH 143 Take Home Exam 2
Electrochemistry, Transition, Nuclear
Students may not seek help on this exam from anyone but April Mixon
9.) When a clean iron nail is placed in an aqueous solution of copper (II) sulfate, the nail
immediately begins to become coated with a brownish-black solid. In a few minutes, the entire
nail is completely coated with this material. (6 pts)
a. Write a balanced equation for this reaction
b. Calculate Eocell for this reaction What is the material covering the nail and explain how
you know this
c. Can the reaction be made into a voltaic cell, why or why not?
d. What are the oxidizing and reducing agents?
10.) Name the following species (8 pts)
a. [Cr(NH3)6][Cr(CN)5Cl]
b. [Co(NH3)4(H2O)Br]Br2
c. K[Ag(CN)2]
11.) Write formulas for the following (5 pts)
a. Diamminediaquabromochloroaluminum sulfate
b. Potassium hexacyanoferrate (II)
12.) Draw the orbital energy splitting diagrams and use the spectrochemical series to show how the
electrons would fill the orbitals (clearly number your electrons as you fill in the orbitals) for each
of the following (assume water is weak): Identify the complex as either being high spin or low
spin, in 1 sentence (each), briefly explain why you chose high spin or low spin (15 pts):
a. [Cu(CN)4]-2 (square planar)
b. [FeCl2(H2O)4]+1
c. [Co(CO)6]+3
13.) Three coordination complexes formed by Co+3 are [Co(H2O)6]+3, [Co(NH3)6]+3, and [CoF6]-3. Each
of these ions will absorb light of a different color. One will absorb red light, the other orange
light, and another blue-green light. Using your knowledge of splitting diagrams and strong and
weak field ligands, pair up the complex with the color it will absorb and briefly justify your
choice. (9 pts)
14.) Write a balanced nuclear equation for each of the following: (6 pts)
a. Electron capture by neptunium-232
b. Alpha decay of 212
83 Bi
c. Positron emission by
12
7N
3
CH 143 Take Home Exam 2
Electrochemistry, Transition, Nuclear
Students may not seek help on this exam from anyone but April Mixon
You may directly answer these questions on these sheets.
Multiple Choice (1 pt each) Write the letter on the line.
____
1.
a.
b.
c.
d.
Rank the subatomic particles from lowest to highest mass?
electrons < neutrons < protons
electrons < protons  neutrons
neutrons < electrons < protons
electrons = protons < neutrons
____
2.
a.
b.
c.
d.
e.
What is the molar mass of dinitrogen trioxide?
76.01 g/mol
30.01 g/mol
92.01 g/mol
44.02 g/mol
108.0 g/mol
____
3.
a.
b.
c.
d.
e.
Which of the following compounds are likely to be soluble in water: Ni(OH)2, ZnCl2, CuS,
Fe2(CO3)3, AgCl, and Pb(NO3)2?
ZnCl2
ZnCl2 and Pb(NO3)2
CuS and AgCl
Fe2(CO3)3 and Ni(OH)2
none of the compounds are soluble
____
4.
a.
b.
c.
d.
e.
Which of the following compounds is a weak acid?
HCl
HF
HBr
HNO3
HClO4
____
5.
a.
b.
c.
d.
e.
What is the oxidation number of manganese in KMnO4?
-2
0
+3
+5
+7
____
6.
Planck suggested that all energy gained or lost by an atom must be some integral multiple
of a minimum amount of energy called a ________.
quantum
spectra
photon
vibration
Bohr
a.
b.
c.
d.
e.
4
CH 143 Take Home Exam 2
Electrochemistry, Transition, Nuclear
Students may not seek help on this exam from anyone but April Mixon
____
7.
a.
b.
c.
d.
e.
What type of orbital is designated n = 4, l = 2, ml = +1?
4s
4p
4d
2f
None
____
8.
A substance that contains unpaired electrons is attracted to a magnetic field. This
substance is said to be ________.
Ionic
Ferromagnetic
Paramagnetic
Polar
Diamagnetic
a.
b.
c.
d.
e.
____
a.
b.
c.
d.
e.
What types of elements have atomic radii which remain relatively constant across a
period?
metallic main group elements
Semiconductors
nonmetal main group elements
transition metal elements
none of the above
____
10.
a.
b.
c.
d.
e.
Which type of elements have no affinity for electrons?
transition metals
main group metals
noble gases
main group nonmetals
Semiconductors
____
11.
How many sigma () bonds and pi () bonds are in the following molecule?
a.
b.
c.
d.
e.
seven  and two 
six  and two 
eleven  and zero 
nine  and two 
two  and nine 
12.
a.
b.
c.
d.
e.
Which substance has cations bonded together by mobile electrons?
KCl(s)
O2(g)
Mg(s)
Si
SiO2
____
9.
5