Question

How does electrolysis chemistry work?

Answer 1

Electrolysis is the passing of a direct electric current through on electrolyte producing chemical reactions at the electrodes and decomposition of the materials.

Complete step by step answer:
Electrolysis is commercially important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell.
The main components required to achieve electrolysis are an electrolyte, electrodes and external power source. A partition is optional to keep the products from diffusing to the vicinity of the opposite electrode. The electrolyte is a conductive ionic chemical substance which contains free ions and carries electric current.
The electrodes are separated by a distance such that a current flows between them through electrolyte and are converted to the power source which completes the electrical circuit. Electrodes are immersed in electrolyte.
Process of electrolysis: (1) Electrolysis is the interchange of atoms and by the removal or addition of electrons due to applied current.
(2) Each electrode attracts ions that are of the opposite charge. Positively charged ions move towards the electron providing cathode. Negatively charged ions move towards the electron extracting anode.
(3) In this process electrons are effectively introduced at the cathode as a reactant and removed at the anode as a product.
(4) When electrodes lose or gain electrons they may dissolve in the electrolyte and react with other ions.
(5) When ions gain or lose electrons and become neutral, they may form compounds that separate from the electrolyte. Positive metal ions like $C{u^{2 + }}$ deposit onto the cathode in a layer. The term for this is electroplating.

Additional Information:
Michal Faraday introduced electrolysis electrochemical cells including the hydrogen fuel cell, using the difference in standard electrode potential to generate an electric potential that provides useful power. Though related to the interaction of ions and electrodes, electrolysis and the operation of electrochemical cells are quite distinct. Electroplating is used in many industries for either functional or decorative purposes, as in vehicle bodies and nickel coins. Electrochemical machining, where an electrolytic cathode is used as a shaped tool for removing material by anodic oxidation from a shaped tool for removing material by anodic oxidation from a work piece. The voltage required to electrolyze a salt solution can be derived from the standard electrode potential for the reaction at anode and cathode. The standard electrode potential is directly related to the Gibbs free energy, $\Delta G$ for the reactions at electrodes and refers to an electrode with no current flowing.

Note: The desired products of electrolysis are often in a different physical state from the electrolyte and can be removed by physical process. The quantity of the products is proportional to the current, and when two or more electrolytics are connected in series to the same power source, the product produced in the cells are proportional to their equivalent weight. These are known as Faraday’s Laws of electrolysis. Electrodes of metal, graphite and semiconductor materials are widely used.
Choice of suitable electrode depends on chemical reactivity between the electrode and electrolyte. Oxidation of ions or neutral molecules occurs at the anode. Reduction of neutral molecules occurs at the cathode. Sometimes the solvent themselves are oxidized or reduced at the electrodes. It is even possible to have electrolysis involving gases. E.g. by using a gas diffusion electrode.