SPM Form 4: Electrochemistry (Checklist)

• Electrode: A conductor in the form of a wire, rod or plate which carry electric current in and out of an electrolyte during electrolysis.
• Electrolyte: A substances that can conduct electricity in molten state or aqueous solution and is decomposed by electric current.
• Non-electrolyte: A substances that cannot conduct electricity in molten state or aqueous solution.
• Anion: A negatively-charged ion.
• Cation: A positively-charged ion.
• Anode: An electrode which is connected to the positive terminal of the source of electricity during electrolysis. (donation of electrons)
• Cathode: An electrode which is connected to the negative terminal of the source of electricity during electrolysis. (acceptance of electrons)
• Electrolysis: The process whereby a compound is broken down into its constituent elements when electricity is passed through an electrolyte.
• Aqueous solution: A solution produced when a compound is dissolved in water.
• Electrochemical series: An arrangement of metals based on the tendency of each metal to donate electrons.
• The lower the position of an ion in the electrochemical series, the higher is the tendency of the ions to be discharged.
• Purification of metals: The process of obtaining a pure metal from an impure metal through electrolysis. E.g. Impure copper can be purified through electrolysis when the impure copper is used as the anode and a pure copper is used as the cathode.
• Electroplating of metals: The process of coating a layer of metal onto another metal using electrolysis.
• Simple voltaic acid: A cell that converts chemical energy to electrical energy. The chemical reactions in a simple voltaic cell produce electricity. No current flow will flow if both electrodes are made of the same metal.
• Electropositivity: A measurement of the ability of an atom to donate electrons to form a positive ion.
• Displacement reaction: A reaction where a more electropositive metal displace another metal from its salt solution. A metal which has a higher position in the electrochemical series is able to displace the metal below it in the series from their salt solutions.