3.3.4 Alkenes Flashcards
(17 cards)
π bonds
-Bond 2
-electrons in region above and below σ bond
-cannot rotate bond without breaking
-only in double/triple bonds
σ bonds
-Bond 1
-electrons in space between nuclei of atom
-single bonds are σ only (H—H)
-allows free rotation
structural isomerism definition?
molecules with the same molecular formula but a different structural formula
3 examples of structural isomerism?
- Chain Isomers (different carbon chain)
- Position Isomers (functional group in different position)
- Functional Group Isomers (different functions group)
stereoisomerism definition?
molecules with same molecular and structural formulas but different arrangement of atoms in space
2 examples of stereoisomerism?
- E-Z Isomers - caused by molecules with C=C with 2 different groups attached to each C=C
- Optical Isomers - caused by C with atoms having 4 different group attached leading to molecules that are non superimposable mirror images of eachother
Rules to determine whether E or Z Isomer?
-greater atomic number = higher priority
if higher priority is on:
Z - same side
E - opposite
-always follow chain if they have same atomic number
why are alkenes susceptible to attack by electrophiles?
C=C is very electron rich due to π bonds
MAJOR product?
-secondary carbocation is more stable
-extra alkyl group which is electron releasing
MINOR product?
-primary carbocation is less stable
-only receiving electron density from one alkyl group
name of process in which monomers join together?
polymerisation
polymer
long chain molecule made from lots of small molecules joined together
monomer
small molecules that join together to make polymers
addition polymerisation
formation of long chain molecules from lots of small molecules joined together with no other products
hydrolysis
a reaction where the molecule is split by the addition of water
hydration
a reaction where water is added to a molecule
testing for alkenes with bromine water?
add bromine water
orange - clear = presence of C=C bond
