Complete combustion
Alkanes burn completely in excess oxygen to form carbon dioxide and water.
- Reagents
- oxygen
- Conditions
- ignite in excess oxygen
- Reaction class
- combustion
- Equation
- CnH(2n+2) + ((3n+1)/2)O2 -> nCO2 + (n+1)H2O
Overview
Alkanes burn completely in excess oxygen to form carbon dioxide and water.
Transformation
- Equation
- CnH(2n+2) + ((3n+1)/2)O2 -> nCO2 + (n+1)H2O
- Reagents
- oxygen
- Environment
- ignite in excess oxygen
- Reaction class
- combustion
- Mechanism
- combustion
- Evidence level
- textbook core
Scope and limitations
- Scope
- Alkanes undergo complete combustion in excess oxygen to form carbon dioxide and water.
- Limitations
- The displayed general equation is for an acyclic alkane. Limited oxygen gives carbon monoxide and/or carbon.
Related reactions
- Free radical chlorination: Alkanes → Chloroalkanes
Photochemical chlorination can convert alkanes into chloroalkanes.
- Free radical bromination: Alkanes → Bromoalkanes
Photochemical bromination can convert alkanes into bromoalkanes.
- Cracking: Alkanes → Alkenes
Thermal or catalytic cracking converts long-chain alkanes into shorter molecules including alkenes.
- Hydrogenation: Alkenes → Alkanes
Hydrogenation reduces alkenes to alkanes.
- Grignard carboxylation co reactant: Carbon dioxide → Carboxylic acids
Carbon dioxide plus a Grignard reagent gives a carboxylic acid after acidic work-up.
- Complete combustion: Alcohols → Carbon dioxide
Alcohols burn completely in excess oxygen to form carbon dioxide and water.
- Combustion: Benzene → Carbon dioxide
Benzene combusts to carbon dioxide and water and tends to burn with a smoky flame.
References
- Pearson Edexcel Level 3 Advanced GCE in Chemistry specificationPearson Education Limited · Pearson qualifications · 2024
Supports the textbook-core organic reaction routes used for displayed route and mechanism content.