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Electrolysis is a process that uses electricity to drive a chemical reaction that wouldn't normally happen on its own. A direct current (DC) is passed through a substance, causing it to break down into its parts. This is important in separating elements from their natural sources, like refining metals from ores.

Electrolysis is a method for permanently removing unwanted hair. A thin probe is inserted into the hair follicle, and an electric current is used to destroy the hair growth center. This is the only method approved by the FDA for permanent hair removal, although other options like laser hair removal are available.

• The minimum voltage required to initiate electrolysis for a specific substance is called the decomposition potential.

• Electrolysis plays a crucial role in various industries and technologies.

• Electrolyte: This is the conductive medium that allows ions to flow freely. Examples include saltwater, solutions with dissolved salts or even molten metals.

• Electrodes: These are two electrical conductors that are submerged in the electrolyte. They act as the entry and exit points for the electric current.

  • Anode: The positive electrode where negatively charged ions (anions) are attracted and undergo oxidation (lose electrons).

  • Cathode: The negative electrode where positively charged ions (cations) are attracted and undergo reduction (gain electrons).

• When a direct current (DC) is applied to the electrodes, it creates an electric field within the electrolyte.

• The charged ions in the electrolyte are attracted to the oppositely charged electrodes.

Reactions at the Electrodes:

• Anode: Anions migrate towards the anode. Depending on the specific reaction, the anions may lose electrons (oxidation) and become part of the electrode or react with the electrolyte to produce a gas.

• Cathode: Cations migrate towards the cathode. They gain electrons (reduction) and can be:

  • Deposited on the cathode (plating) if it's a metal ion.

  • Decomposed into simpler substances if it's a molecule.

Examples of Electrolysis:

• Water Electrolysis: Splitting water (H2O) into hydrogen gas (H2) and oxygen gas (O2) using electricity.

• Electroplating:  Depositing a thin layer of metal onto another surface, used in jewelry making and for protecting metals from corrosion.

• Metal Refining: Separating pure metals from their ores by passing electricity through a molten metal solution.

Overall Effect:

The specific chemical reaction that occurs during electrolysis depends on the composition of the electrolyte and the electrode materials. However, the general principle is that electrical energy is used to drive a non-spontaneous chemical reaction, separating the components of a compound or extracting a desired element.