Electrochemistry: Practice Questions

In the electrolysis of concentrated sodium chloride solution using inert electrodes, which species is selectively discharged at the anode?

In a simple electrochemical cell, two different metal electrodes are dipped into an electrolyte. If the metals used are magnesium and copper, which statement is correct?

During the electrolysis of concentrated aqueous sodium chloride using inert electrodes, how do the pH of the electrolyte and the identity of the gas at the anode change?

In a hydrogen fuel cell, what is the overall chemical change that generates electricity?

Which of the following observations is made during the electrolysis of dilute aqueous sodium chloride using platinum electrodes?

During the electrolysis of concentrated aqueous sodium chloride using inert graphite electrodes, chlorine gas is evolved at the anode. Explain why hydroxide ions are not preferentially discharged at the anode despite having a greater ease of discharge than chloride ions.

A simple electrochemical cell is constructed using a Magnesium electrode and a Copper electrode immersed in an electrolyte of dilute sulfuric acid, as shown in the diagram. Predict the polarity of the Magnesium electrode and explain how the movement of electrons in the external circuit generates electrical energy.

A student performs the electrolysis of concentrated aqueous sodium chloride using carbon electrodes.

(a) List all the cations and anions present in the electrolyte.
(b) Identify the products formed at the anode and the cathode.
(c) Construct the ionic half-equations for the reactions occurring at both electrodes, including state symbols.
(d) After the electrolysis has proceeded for some time, the remaining solution is tested with Universal Indicator. Predict the color change and explain your answer based on the ions remaining in the solution.