3.3.4 - Alkenes Flashcards
What are the two parts that make up double bond
Bond 1 = Covalent bond there are 2 electrons between C atoms
Bond 2= Pi bond formed from the overlap of P orbitals
What is stereoisomerism
Molecules with the same molecular and structural formula but with different arrangement of atoms
What are geometric isomers
Caused by molecules with a C=C with two different groups attached to each C
What are E-Z isomers
Geometric isomers were nothing can rotate around C=C
What are the CIP priority rules
E - if priority are on opposite sides
Z- if priority are on same side
What are structural isomers
Molecules with the same molecular formula but different structural formula
Three types of structural isomers
Chain isomers
Position isomers
Functional group isomers
What are chain isomers
Caused by having a different carbon chain
What are position isomers
Caused by functional groups being in a different position
What are functional group isomers
Caused having different functional groups
What are alkenes
Unsaturated hydrocarbons
What reactions can occur with alkenes
Electrophilic addition
Addition polymerisation
Why are they attacked by electrophiles
Have a high electron density because of double carbon bond
Electrophiles that work on alkenes
Br2
HBr
H2O
H2SO4
Draw the reaction between Br2 and a symmetrical alkene
Draw
Why can be Br2 be an electrophile
Because the double bond can induce a temporary dipole
Draw an electrophilic addition between HBr and symmetrical alkenes
Draw
Draw an electrophilic addition between unsymmetrical alkene
Draw
What happens when unsymmetrical alkene undergo electrophilic addition
They produce a major and a minor product
Draw what happens in electrophilic addition with H2SO4 with symmetrical alkenes
Draw
What happens after electrophilic addition with H2SO4 has occurred
Hydrolysis which make it into a alcohol with H2SO4 t
Draw What happens in electrophilic addition with a unsymmetrical alkene using H2SO4
Draw
What is need to be with water for electrophilic addition to occur
H2O with the presence of a strong acid
Draw what happen in electrophilic addition with H2O
Draw
Explain what happen with alkenes for the order of formation
Carbon cations form in order of preference. The 3 carboncation is more stable than 2 carbon cation and is formed in preference
What happens in the bromine test
Bromine water Turn orange to colourless in presence of alkene
What is a polymer
Long chain molecules made from lots of small molecules joined together
What is a monomer
Small molecules that join together to make polymers
What is addition polymerisation
Formation of long chain molecules from lots of small molecules jointing together with no other product
Draw PVC
Draw
What is PVC proper name
Poly (chloroethene)
What are the uses of polychloroethene
Window frames
Pipes
Clothing
Insulation in wires
