Redox Review

Create a Venn Diagram for Voltaic and Electrolytic cells

Explain how a voltaic cell between Iron (III) and lead (II) works. Then represent the cell in short hand notation A voltaic cell includes 2 half cells, a salt bridge, wires, and a voltmeter Each half cell contains a metal electrode and a salt solution of that same metal Lead (II) is more reactive than iron (III) so the lead will be the oxidation half cell. The oxidation half cell is the anode which is negative because the lead strip is losing lead cations to the solution and retaining the electrons which are then transferred over to the cathode. Ion concentration in solution increases which causes build up of + ions to transfer from anode to cathode via the salt bridge The actual anode is decreasing in mass because it is losing the metal ions The cathode is positive because the electrons are pulled over due to the positive iron ions hitting the metal strip. These ions combine with the electrons to be reduced into neutral metal that plates the electrode. The actual cathode is increasing in mass as the newly reduced metal atoms are layering on the existing metal The cation concentration is reduced due to them reacting with electrons transferred to the cathode. This results in transfer of anions in solution from the cathode to the anode through the salt bridge ALSO WRITE THE HALF REACTIONS TO BE SAFE

Draw an electrolytic cell with zinc electrodes and sodium fluoride electrolyte

Outline the process happening in an electrolytic cell containing molten zinc chloride Electrolytic cell contains 2 inert electrodes in an electrolyte that is undergoing electrolysis. The ions in the electrolyte will lose their charge The electrodes are attached to a battery to provide electrons to start the redox process The electrode attached to the negative side of the battery will attract the positive zinc ions in solution. The zinc ions will bond with the electrons leaving the battery to produce neutral zinc atoms. This is reduction so this is the cathode The electrode attached to the positive side of the battery will attract the negative chlorine ions in solution. The positive electrode will steal electrons from the chlorine ions to produce neutral chlorine gas. This is oxidation so this is the anode.

Practice-Balance in Acidic Cu + NO 3 -1  Cu +2 + NO

Mn +2 + NaBiO 3  Bi +3 + MnO 4 -

H 3 AsO 4 + Zn  AsH 3 + Zn +2