1. Erasmus+ Oxidation and Reduction Sustainabilityby Biotechnology Renée Ristl Evelin Szabados

2. Definition • Oxidation: electrondonation • Reduction: electronacceptance • Example: • Oxidation: 2 O2- O2 + 4 e- • Reduction: Fe3+ + e- Fe2+ • Both, oxidationandreductionhavetooccurtogether!

3. Oxidation numbers • Oftentherearen‘t “real“ molecularcharges – e.g. glucoseorwater • Atoms possess an oxidationstate, describedbyoxidationnumbers • H2, O2are neutral  oxidationnumber 0 • In water (H2O), the H hasgottheoxidationnumber +1, the O: -2 • In organiccompounds, theoxidationnumberof C hastobecalculated

4. Calculation: Oxidation numberof C • E.g. glucose: -2 +1 +1 • +1 – 2 = -1 • C is neutral •  itneeds+1toequalise

5. Examples +1 0 Oxidation: 2 H2 4 H+ + 4 e- Together: 2 H2 + O2 2 H2O -2 0 Reduction: O2 + 4 e- 2 O2- +3 +1 Oxidation: + 2 e-  R R