H

Homolytic Cleavage

A-B → A• + B• (radical cleavage)
AllChemicals — The Online Chemical Glossary | https://allchemicals.info/chemical/504-homolytic-cleavage
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Quick Reference
Formula / NotationA-B → A• + B• (radical cleavage)
Also Known AsHomolysis, radical cleavage, symmetric bond cleavage, free radical generation

What is Homolytic Cleavage?

The breaking of a covalent bond in which each atom takes one of the shared electrons, producing two neutral radicals. This type of bond cleavage occurs in radical reactions, including free radical halogenation of alkanes and combustion processes.

Formula & Notation

A-B → A• + B• (radical cleavage)

Other Names / Synonyms: Homolysis, radical cleavage, symmetric bond cleavage, free radical generation

Properties & Characteristics

Homolytic cleavage (homolysis) is the breaking of a covalent bond in which each fragment retains one electron, producing two radicals. It occurs preferentially when bond energies are moderate, radical stability is high (tertiary, allylic, benzylic), or when energy is supplied as heat or light (photolysis). Homolysis is favoured in low-polarity media and at high temperatures. Contrast with heterolytic cleavage, which produces ions.

Uses & Applications

Homolytic cleavage initiates radical chain reactions: combustion, radical halogenation of alkanes (Cl₂ + hν → 2Cl•), polymerisation (peroxide initiators undergo homolysis), and industrial processes like steam cracking. In biology, homolytic cleavage of O-O bonds in peroxides generates reactive oxygen species (ROS).

Safety Information

Homolytic reactions can be self-sustaining chain reactions. Peroxides (which readily undergo homolysis) are shock-sensitive and can explode. Organic peroxides must be stored at low temperature, away from reducing agents, and used before expiry. Radical reactions in flammable solvents must be conducted away from ignition sources.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Homolytic Cleavage
Formula A-B → A• + B• (radical cleavage)
Index All "H" terms
Synonyms Homolysis, radical cleavage, symmetric bond cleavage, free radical generation

Frequently Asked Questions

The breaking of a covalent bond in which each atom takes one of the shared electrons, producing two neutral radicals. This type of bond cleavage occurs in radical reactions, including free radical halogenation of alkanes and combustion processes.

More "H" Terms

1-Hexanol C6H14O 2-Hydroxyethyl methacrylate C6H10O3 4-Hydroxybenzaldehyde C7H6O2 Haber Process N₂ + 3H₂ ⇌ 2NH₃ | ΔH = −92 kJ/mol Hafnium Hf Half Cell Half Life Half-Cell E = E° − (RT/nF)lnQ Half-Life A(t) = A₀e^(−λt); t½ = ln2/λ Half-Reaction Halide X⁻ (e.g., F⁻, Cl⁻, Br⁻, I⁻) Halogen F₂, Cl₂, Br₂, I₂, At; Group 17; ns²np⁵ valence configuration
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Editorial standards: Chemical data is sourced from peer-reviewed literature, CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA, and IAEA. For educational purposes only — always consult official SDS documentation and qualified professionals before handling chemicals.

AllChemicals.info — The Online Chemical Glossary | https://allchemicals.info/chemical/504-homolytic-cleavage

For educational purposes only. Verify all information before use.