Chemistry 2000 Practice Problems on Electrochemistry

Some of these problems may require data from the textbook or other sources for their solution.

1. Dissolved carbon dioxide reacts with calcium metal in a basic aqueous environment to produce oxalate ions and calcium ions. Balance the reaction.
2. Consider the electrochemical cell

   

   The zinc and copper solutions are both produced by dissolving the appropriate sulfates. The concentration of zinc sulfate in the left half-cell is 0.005mol/L and the concentration of copper sulfate in the right half-cell is 0.002mol/L. Calculate the voltage produced by this cell at 298K.

3. The highest voltages which can be produced electrochemically are in the range of 5-6V. Consider the following cell:

   

   The lithium fluoride concentration is 0.5mol/L and fluorine is bubbled past the inert electrode at a pressure of 1atm. Calculate the voltage produced by this cell at 298K.

4. An acidified solution of sodium iodate ( ) with an iodate concentration of 0.04mol/L and a pH of 4 is prepared. This solution is used to operate an electrochemical cell, the other half-cell being the standard hydrogen electrode. The two half-cells share a common solution; the separation of reactants is achieved by simply bubbling the hydrogen gas at a pressure of 1atm over one electrode and not the other. A brown colour appears at the iodate electrode, indicating the formation of molecular iodine.
   1. Balance the reaction.
   2. After a few seconds, a spectroscopic measurement of the iodine concentration is made. It is found that the iodine concentration is . If the cell generates a voltage of 1.090V at that time and the operating temperature is 298K, what is the standard reduction potential corresponding to the iodate half-reaction?