4.1.3 Alkenes Flashcards
What are alkenes?
Unsaturated hydrocarbons that contain at least one C=C bond made up of a pi bond and a sigma bond
What is the general formula of alkenes?
CnH2n
How is a Pi bond formed?
Electrons in the adjacent P orbitals overlap above and below the carbon atoms. They can only be made after a sigma bond is formed
What bond restricts the rotation of carbon atoms?
Pi bond
What is the angle and shape of a double bond?
Trigonal planar, 120 degrees
Are alkenes more or less reactive than alkanes and why?
More reactive due to high electron density of double bond and the fact the pi-bond is slightly easier to break
What intermolecular forces of attraction do alkenes have?
only london forces due to non-polar bonds
Are alkenes soluble in water? Why?
No, due to the non-polar bonds
What are the types of isomers that can be formed using alkenes?
- E/Z isomers - due to the restricted rotation
- Cis-trans isomers - if two of the same substituents are attached to each carbon
What is an electrophile?
species that are electron pair acceptors
What conditions are needed for the electrophilic addition of H2O to an alkene? What is this reaction called?
Hydration - steam in the presence of an acid catalyst, usually phosphoric acid
What are the productions of the hydration reaction?
An alcohol
