Topic 4 - Electrolysis

(a) *describe electrolysis as the conduction of electricity by an ionic compound (an electrolyte), when molten or dissolved in water, leading to the decomposition of the electrolyte
(b) *describe electrolysis as evidence for the existence of ions which are held in a lattice when solid but which are free to move when molten or in solution
(c) describe, in terms of the mobility of ions present and the electrode products, the electrolysis of molten lead bromide, using inert electrodes
(d) predict the likely products of the electrolysis of a molten compound
(e) apply the idea of selective discharge (linked to the reactivity series for cations, see 9.2) to deduce the electrolysis of concentrated aqueous sodium chloride,

aqueous copper(II) sulfate

and dilute sulfuric acid using inert electrodes

(f) predict the likely products of the electrolysis of an aqueous electrolyte, given relevant information

(g) construct equations for the reactions occurring at each electrode during electrolysis

(h) *describe the electrolysis of purified aluminium oxide dissolved in molten cryolite as the method of extraction of aluminium (see 9.5(a))

(i) *describe the electrolysis of aqueous copper(II) sulfate with copper electrodes as a means of purifying copper

(j) *describe the electroplating of metals, e.g. copper plating, and recall one use of electroplating

(k) describe the production of electrical energy from simple cells (i.e. two electrodes in an electrolyte) linked to the reactivity series (see 9.2)