Question

How are redox reactions involved in electrolysis?

Answer 1

Hint: A reaction in which the oxidation process or the loss of electrons and the reduction process or the gain of electrons occur simultaneously and the electrons are transferred between two species is known as a redox reaction or an oxidation-reduction reaction.

Complete step by step answer: When a direct electric current is passed to produce an otherwise non-spontaneous chemical reaction is known as electrolysis.
There occurs a chemical reaction at the electrodes along with the decomposition of the materials when the current is passed through an electrolyte.
The main process of electrolysis is the exchange of ions and atoms by the addition or removal of electrons due to the current applied.
Ions of opposite charge are attracted by the electrodes.
Anions that are negatively charged move towards the electron-extracting positive anode. At the anode, electrons are removed as a product, and this process is known as oxidation. For example, oxidation of ferrous ions to ferric ions takes place at the anode.
     \[F{{e}^{2+}}(aq)\to F{{e}^{3+}}(aq)+{{e}^{-}}\]
Cations that are positively charged move towards the electron-providing negative cathode. At the cathode, electrons are introduced as a reactant and this process is known as reduction. For example, ferricyanide ions can be reduced to ferrocyanide ions at the cathode.
     \[Fe(CN)_{6}^{3-}+{{e}^{-}}\to Fe(CN)_{6}^{4-}\]
Since the process of oxidation and reduction takes place during an electrolysis reaction, we can say that electrolysis is a type of redox reaction.

Additional Information: Electrolysis can be used for various processes like:
- Extraction of metals (electrometallurgy) such as aluminum, magnesium, sodium, calcium, potassium, etc.
- Production of non-metals like fluorine, hydrogen, chlorine, etc.
- Metal refining
- Production of chemicals like chlorine gas, caustic soda (NaOH), etc
- Electroplating
- Electrotyping
- Electroforming
- Electro-cleaning
- Equivalent elemental mass determination
- Determination of coated layer thickness

Note: It must be noted that neutral molecules can react at either of the electrodes. During electrolysis, when electrons are gained or lost by the neutral atoms or molecules on the electrode's surface, they become ions. They dissolve in the electrolyte and react with other ions.