Brainlag PlusThe alkenes and their general formula, the C=C double bond, and what forms when hydrogen, steam or a halogen adds across it.
The alkenes
Alkenes are hydrocarbons with one C=C double bond.
They form a homologous series with the general formula:
alkenes: CnH2n
Ethene C2H4, propene C3H6, butene C4H8, pentene C5H10. There is no "methene": you need two carbons to make a double bond.
Alkenes burn like alkanes, but often with a smokier flame, because more of the carbon is left unburnt.
The rest of this lesson and its 11 practice questions are in Plus.
Screen 1 of 4, free to read.
- 11 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards