Syllabus Objectives – Electrolysis

Self Assessment Checklist

Electrolysis I can do this!
(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 of the structure of ionic compounds in solid (ions which are held in a lattice), molten and aqueous states (ions are free to move).  
(c) Describe, in terms of the mobility of ions present and the electrode products, the electrolysis of molten sodium chloride, using inert electrodes.  
(d) Predict the likely products of the electrolysis of a molten binary compound.  
(e) Predict the likely products of the electrolysis of an aqueous electrolyte using the idea of selective discharge of ions.  
(f) Apply the idea of selective discharge based on  
(i) cations: linked to the reactivity series,  
(ii) anions: halides, hydroxides and sulfates (e.g. aqueous copper(II) sulfate and dilute sodium chloride solution (as essentially the electrolysis of water)),  
(iii) concentration effects (as in the electrolysis of concentrated and dilute aqueous sodium chloride.  
(In all cases above, inert electrodes are used.)  
(g) Construct ionic equations for the reactions occurring at the electrodes during the electrolysis, given relevant information.  
(h) Describe the electrolysis of aqueous copper(II) sulfate with copper electrodes as a means of purifying copper.  
(i) Describe the electroplating of metals, e.g. copper plating, and state one use of electroplating.  
(j) Describe the production of electrical energy from simple cells (i.e. two electrodes in an electrolyte) linked to the reactivity series and redox reactions (in terms of electron transfer).