Redox Reactions This is a oxidation-reduction reaction where the transfer of electrons from a reductant to an oxidant occur. Oxidation- is the loss of electrons therefore this element is being reduced. (reductant) Reduction- is the gain of electrons therefore this element is being oxidised. (oxidant)

Oxidation Like acid-base reactions, redox reactions are a matched set - you don't have an oxidation reaction without a reduction reaction happening at the same time. So we call these half cell reactions. Hence we need to half reactions to complete it as a whole. Cu (s) ----> Cu e - This half-equation says that we have solid copper with no charge, being oxidized so losing electrons to form a copper ion with a 2+. This is an example of a metal changing into a metal salt.

Reduction Here, two silver ions with a positive charge are being reduced through the addition of two electrons to form solid silver. 2 Ag + (aq) + 2 e > 2 Ag (s) This reaction shows that a metal salt is being displaced from the aqueous solution and forming into it metal state.

Overall equation Cu (s) ----> Cu e - 2 Ag + (aq) + 2 e > 2 Ag (s) Cu (s) + 2 Ag + (aq) + 2 e > Cu e Ag (s) Cu (s) + 2 Ag + (aq) > Cu Ag (s)

Electrochemical series This is a table that classifies the strengths of increasing oxidising and reducing agents in redox reactions. Refer to hand out of electrochemical series

Looking more closely s07.sci.phys.matter.metalshcl/ s07.sci.phys.matter.metalshcl/ Lets practice writing the oxidation, reduction and overall reactions