Redox Titrations

• Redox titrations are a method used to determine the oxidising or reducing capacity of a solution.

• In these titrations, redox reactions occur between the analyte and titrant. Oxidation is the loss of electrons while reduction is the gain of electrons.

• Redox titrations often involve the use of a redox indicator to identify the equivalence point where moles of oxidising agent equals moles of reducing agent.

• Transition metals often serve as redox indicators due to the clear colour changes associated with their differing oxidation states.

• Equation balancing in redox reactions includes maintaining balance in terms of both atoms and charges.

• Certain redox reactions may require an acidic or alkaline medium to proceed, such as the redox reaction involving permanganate ions and hydrogen peroxide.

• A redox couple refers to a reduced species and its corresponding oxidised form, such as Fe3+/Fe2+.

• In a redox titration, a potentiometer can be used to measure the emf (electromotive force) change, signalling the end point of the reaction.

• Key concepts to understand in redox titrations include: oxidation number, half reactions, redox couples, equivalence point and standard solution.

• Half-cells are another important aspect of redox reactions, wherein one half of the cell houses the oxidation, while the other half houses the reduction.

• Redox titrations can be used to analyse real-world samples for concentrations of oxidising or reducing agents—examples include the determination of iron content in an iron supplement or the determination of vitamin C concentration in orange juice.

• The Nernst equation is critical for understanding redox titrations, becoming crucial when calculating equilibrium concentrations and potentials.