Bromination of Ethylene

C₂H₄ + Br₂ → C₂H₄Br₂

Aperçu

Ethylene reacts with bromine in an electrophilic addition reaction to form 1,2-dibromoethane. The brown color of bromine water is decolorized instantly, making this the classic qualitative test for unsaturation (C=C double bonds). The mechanism involves a cyclic bromonium ion intermediate.

Participants

Rôle	Substance	Coefficient	État
Réactif	Ethylene C₂H₄	1	(g)
Réactif	Bromine Br	1	(l)

Exemple du quotidien

The bromine water test for alkenes is one of the most dramatic color-change tests in organic chemistry: brown instantly becomes colorless.

Importance industrielle

1,2-Dibromoethane was historically used as a lead scavenger in leaded gasoline and is now an important chemical intermediate.

Propriétés

Type: Organic
Réversible: Non
Énergie: Exothermique
ΔH: -121,0 kJ/mol

Réactions associées

Epoxidation of Alkenes (mCPBA) Swern Oxidation Oxidation of Secondary Alcohol to Ketone E2 Elimination (Dehydrohalogenation) Claisen Condensation (Ethyl Acetate) Aldol Condensation of Acetaldehyde Kolbe Electrolysis Baeyer-Villiger Oxidation Beckmann Rearrangement (Cyclohexanone Oxime) Dehydration of Ethanol

Frequently Asked Questions

What is the equation for Bromination of Ethylene?

The balanced equation is: C₂H₄ + Br₂ → C₂H₄Br₂.

What type of reaction is Bromination of Ethylene?

Bromination of Ethylene is a organic reaction.

Is Bromination of Ethylene exothermic or endothermic?

Bromination of Ethylene is exothermic (releases energy). The enthalpy change (ΔH) is -121.0 kJ/mol.