Quiz | Electrochemistry

1

Which of the following statements is incorrect?

Reduction occurs at the cathode

All electrochemical reactions involve the transfer of electrons

It is possible to directly measure the voltage of a single electrode

Electrolysis is a technique that uses electric current to drive an otherwise non-spontaneous chemical reaction

2

Which of the following statement about salt bridge is correct?

It is an agar gel through which ions cannot pass

It allows charge balance to be maintained in the cell

It is represented by a single vertical bar in a cell diagram

It drives free electrons from one electrode to the other

3

Why is Standard Hydrogen Electrode (SHE) called as the primary reference electrode?

Its voltage E0 = 0 V

The electrode is a nonreactive metal

Its output potential is independent of the composition of the solution

All of the above

4

What is the reaction of the zinc-copper cell: Zn (s) | ZnSO4(aq) || CuSO4(aq) | Cu(s)?

ZnSO(aq) → Zn2+ (aq) + 2 SO4- (aq)

Zn (s) + Cu2+ (aq) → Cu (s) + Zn2+ (aq)

Cu (s) + Zn2+ (aq) → Zn (s) + Cu2+ (aq)

Cu (s) + ZnSO(aq) → Zn (s) + CuSO(aq)

5

What is the half-reaction that occurs at the anode during the electrolysis of sodium bromide?

Na+ + e- → Na

Na → Na+ + e-

Br2 + 2 e- → 2 Br-

2 Br- → Br2 + 2 e-

6

What is the correct Nernst equation for the reaction: Cu (s) + Zn2+ (aq) → Zn (s) + Cu2+ (aq)?

E = E0 + RT/2F x ln Q

E = E0 – RT/2F x ln Q

E = E0 + RT/F x ln Q

E = E0 – RT/F x ln Q