Alkane

Key Stage 4

Meaning

Alkanes are the simplest form of hydrocarbon compounds with no double bonds and the general formula; C_nH_2n+2

About Alkanes

Alkanes are a homologous series of hydrocarbon compounds.

The functional group of the Alkanes is the single bonds between the Carbon atoms and between the Carbon and Hydrogen atoms.

Alkanes are long chains of Carbon atoms covalently bonded together with single bonds and Hydrogen atoms taking the remaining bonds.

Examples

	Methane	Ethane	Propane	Butane
Chemical Formula (CnH2n+2)	CH4	C2H6	C3H8	C4H10
Structural Formula	CH4	CH3CH3	CH3CH2CH3	CH3CH2CH2CH3
Structural Diagram
Ball and Stick Model

Reactions of Alkanes

Combustion

During combustion of alkanes the Carbon and Hydrogen atoms are oxidised to produce Carbon Dioxide and Water.

Complete Combustion

Complete combustion occurs when there is enough Oxygen to completely Oxidise all of the atoms in the alkane. In the complete combustion of alkanes the only products are Carbon Dioxide and Water.

Methane + Oxygen → Carbon Dioxide + Water

CH₄ + 2O₂ → CO₂ + 2H₂O

Ethane + Oxygen → Carbon Dioxide + Water

2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O

Propane + Oxygen → Carbon Dioxide + Water

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

Butane + Oxygen → Carbon Dioxide + Water

2C₄H₁₀ + 13O₂ → 8CO₂ + 10H₂O

Incomplete Combustion

Incomplete combustion occurs when there is not enough Oxygen to Oxidise all of the atoms in the alkane. During incomplete combustion of alkanes the products may include Carbon (soot) and Carbon Monoxide.

Methane + Oxygen → Soot + Water

CH₄ + O₂ → C + 2H₂O

Methane + Oxygen → Carbon Monoxide + Water

2CH₄ + 3O₂ → 2CO + 4H₂O

Ethane + Oxygen → Soot + Water

2C₂H₆ + 3O₂ → 4C + 6H₂O

Ethane + Oxygen → Carbon Monoxide + Water

2C₂H₆ + 5O₂ → 4CO + 6H₂O

Ethane + Oxygen → Soot + Carbon Monoxide + Water

2C₂H₆ + 4O₂ → 2C + 2CO + 6H₂O

References

AQA

Alkanes, page 146, 148, 149, GCSE Combined Science; The Revision Guide, CGP, AQA

Alkanes, pages 124-126, 130, GCSE Combined Science Trilogy; Chemistry, CGP, AQA

Alkanes, pages 143-4, GCSE Combined Science Trilogy 2, Hodder, AQA

Alkanes, pages 149, 160, GCSE Chemistry; Third Edition, Oxford University Press, AQA

Alkanes, pages 172-3, GCSE Chemistry, Hodder, AQA

Alkanes, pages 188-192, GCSE Combined Science Trilogy; Chemistry, CGP, AQA

Alkanes, pages 220 -224, GCSE Chemistry, CGP, AQA

Alkanes, pages 228-9, 233, 238-9, 236-41, GCSE Chemistry; Student Book, Collins, AQA

Alkanes, pages 75-77, GCSE Chemistry; The Revision Guide, CGP, AQA

Alkanes; Complete combustion of, pages 145-6, GCSE Combined Science Trilogy 2, Hodder, AQA

Alkanes; Cracking, pages 147-8, GCSE Combined Science Trilogy 2, Hodder, AQA

Alkanes; cracking, pages 176-7, GCSE Chemistry, Hodder, AQA

Alkanes; reaction of, 240-1, GCSE Chemistry; Student Book, Collins, AQA'

Alkanes; structure and formulae, 238-9, GCSE Chemistry; Student Book, Collins, AQA'

Alkanes; use as fuels, pages 1744-5, GCSE Chemistry, Hodder, AQA'

Edexcel

Alkane homologous series, pages 268-269, GCSE Combined Science, Pearson Edexcel

Alkanes, page 268, GCSE Combined Science, Pearson Edexcel

Alkanes, pages 137, 138, 140, GCSE Combined Science; The Revision Guide, CGP, Edexcel

Alkanes, pages 154, 172, 178, GCSE Chemistry, Pearson, Edexcel

Alkanes, pages 253, 256, 262, 263, 284-287, GCSE Chemistry, CGP, Edexcel

Alkanes, pages 87, 88, 90, 98, GCSE Chemistry; The Revision Guide, CGP, Edexcel

Alkanes; homologous series, pages 154-155, GCSE Chemistry, Pearson, Edexcel

Alkanes; reactions, pages 174-175, GCSE Chemistry, Pearson, Edexcel

OCR

Alkanes, pages 141, 143, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR

Alkanes, pages 230-231, 238-239, 240, Gateway GCSE Chemistry, Oxford, OCR

Alkanes, pages 88, 92-94, GCSE Chemistry; The Revision Guide, CGP, OCR Gateway