Redox

• Oxidation is the loss of electrons, while reduction is the gain of electrons.
• Oxidation and reduction occur simultaneously in a reaction, known as redox reactions.
• The acronym OILRIG (oxidation is loss, reduction is gain) is used to remember the redox rule.
• Oxidation number gives the oxidation state of an element or ionic substance.
• There are rules for assigning oxidation states to elements, such as the oxidation state of an element being zero and oxygen having an oxidation state of -2.
• Oxidising agents accept electrons and are reduced, while reducing agents donate electrons and are oxidised.
• Half equations are used to show the separate oxidation and reduction reactions in a redox reaction and must be balanced in terms of species and charges.
• oxidation states are the same as the charge of the substance.

  e.g Na+ has an oxidation state of +1
• A disproportionation reaction is a reaction where an element is both oxidised and reduced