1. Consider the following reaction.

Which one of the following correctly identifies the oxidising agent and a conjugate redox pair (in the form oxidising agent/reducing agent)?

2. When the galvanic cell, shoiwn below, is operating

A. total chemical energy is increasing and electrons flow to half-cell A.
B. total chemical energy is increasing and electrons flow to half-cell B.
C. total chemical energy is decreasing and electrons flow to half-cell A
D. total chemical energy is decreasing and electrons flow to half-cell B

Solution

3) Consider the following half-equation.

A galvanic cell is set up using inert electrodes and the following chemicals:
• half-cell 1: 1.0 M acidified solution of potassium iodate/iodine solution (KI0₃(aq) / l₂(aq))
• half-cell 2: oxygen gas, 0₂(g), in an alkaline solution.

Which one of the following statements is correct when the galvanic cell is operating?
A. Hydrogen gas is produced at the cathode.
B. The oxidising agent is I0₃ ^- and the reducing agent is 0₂.
C. The concentration of OH^- ions decreases at the negative electrode.
D. The mass of the electrode in half-cell 1 decreases.

Solution

4) In a galvanic cell, copper(II) ions, Cu²⁺, are converted to copper metal, Cu.
What mass of Cu is deposited for each 0.50 mol of electrons transferred in the cell?
A. 1.6 x 10 g
B. 3.2 x 10 g
C. 6.4 x 10 g
D. 1.3 x 10² g

Solution