Which half-reactions represent oxidation

Question

Questions:

Please label the questions with the appropriate numbers to avoid confusion.

1. Which half-reactions represent oxidation and which reduction? Explain your reasoning.

a. Fe→Fe ²⁺ +2 e ^-

b. Ni ⁴⁺ + 2e ^-→ Ni ²⁺

c. 2 H₂O+ 2 e ^-→H₂ + 2 OH^-

2. Explain the difference between a rechargeable battery and one that must be discarded. Contrast a NiCad battery with an alkaline battery in your explanation.

3. Two common units associated with electricity are volts and amps. What does each unit measure?

4. What is the difference between a storage battery and a fuel cell?

5. Some people object to synthetic polymers, saying that polymers are not "natural." Give example of two natural polymers.

6. This is a representation of a small segment of polyethylene. The hydrogen atoms are omitted for the sake of clarity.
    I      I     I     I
    I      I     I     I
    I      I     I     I
---C----C---C---C---
     I     I     I     I
     I     I     I     I
     I     I     I     I
     I     I     I     I

7. Does this representation predict that the carbon-to-carbon-to-carbon bond angles in polyethylene are all 180 degrees? Explain your reasoning.

8. The structure for the styrene monomer:

           H        H
             \      /
           C == C
            /        \
          H                              (a pentagon with a circle inscribed in the middle)

a. Rewrite this shorthand structure showing all of the atoms.
b. What is the molecular formula for styrene?
c. What is the molar mass of a polystyrene molecule consisting of 5000 monomer units?