Organic Chemistry
Alkanes
Hydrocarbon- molecule containing only H and C
Functional group- a group of atoms responsible for the characteristic
reactions of a compound
Homologous series- a series of organic compounds with the same
functional group but each member differing by CH2
Aromatic- benzene ring
Aliphatic- no benzene ring
Alicyclic- cyclical but no benzene ring
Structural isomerism- molecules with the same molecular formula but
different structural formula
1. Position
2. Chain
3. Functional group
As chain length increases the boiling points increase as there are more
electrons per molecule so stronger London forces
Complete combustion: Alkane + oxygen -> co2 and water
Alkane -> haloalkane
- Free radical substitution
- UV light
1. Mixture of products and multiple termination steps
2. Substitution is possible at different points along the chain
Alkenes
Sigma bond- direct overlap of orbitals – stronger than pi – electron
density in the middle
Pi pond- lateral overlap of p orbitals – electron density above and below
the sigma bond
Stereoisomers- same structural formula but different arrangement of
atoms in 3D space.
E/Z isomers:
, - Restricted rotation C=C
- Each carbon atom in the C=C is attached to 2 different groups
The highest priority group with the highest molecular mass will determine
whether its E or Z.
Testing for alkenes: Br2- orange to colourless
Addition reaction: a reactant is added to an unsaturated molecule to
make a saturated molecule
Alkene to alkane- H2 gas 150oc Ni catalyst
Alkene to alcohol- H2O H3PO4 steam
Alkene to haloalkane- electrophilic addition
Electrophile: an atom or group of atoms that is attracted to an electron
rich centre where it accepts a pair of electrons to form a new covalent
bond
The majority product is the one formed from the most stable carbocation-
attached to the most carbon atoms
Addition polymerisation- the formation of a very long molecular chain
by repeated additions of unsaturated alkene monomers
Combusted for energy generation, landfill, stored and recycled
Atom economy= total Mr of useful product/total Mr of all reactants
Percentage yield= actual mass/ theoretical mass
Haloalkanes
Haloalkanes have permanent dipole-dipole forces- stronger than alkanes-
weaker than alcohols since they have hydrogen bonds
Hydrolysis- a chemical reaction involving H20 that causes the breaking of
a bond in a molecule
Heating under reflux: the continual boiling and condensing of a reaction
mixture to ensure that the reaction takes place without the contents
boiling dry
Haloalkane to alcohol: nucleophilic substitution NaOH
Nucleophile: an atom or group of atoms that is attracted to an electron
deficient centre where it donates a lone pair of electrons to form a new
covalent bond
Ozone:
Alkanes
Hydrocarbon- molecule containing only H and C
Functional group- a group of atoms responsible for the characteristic
reactions of a compound
Homologous series- a series of organic compounds with the same
functional group but each member differing by CH2
Aromatic- benzene ring
Aliphatic- no benzene ring
Alicyclic- cyclical but no benzene ring
Structural isomerism- molecules with the same molecular formula but
different structural formula
1. Position
2. Chain
3. Functional group
As chain length increases the boiling points increase as there are more
electrons per molecule so stronger London forces
Complete combustion: Alkane + oxygen -> co2 and water
Alkane -> haloalkane
- Free radical substitution
- UV light
1. Mixture of products and multiple termination steps
2. Substitution is possible at different points along the chain
Alkenes
Sigma bond- direct overlap of orbitals – stronger than pi – electron
density in the middle
Pi pond- lateral overlap of p orbitals – electron density above and below
the sigma bond
Stereoisomers- same structural formula but different arrangement of
atoms in 3D space.
E/Z isomers:
, - Restricted rotation C=C
- Each carbon atom in the C=C is attached to 2 different groups
The highest priority group with the highest molecular mass will determine
whether its E or Z.
Testing for alkenes: Br2- orange to colourless
Addition reaction: a reactant is added to an unsaturated molecule to
make a saturated molecule
Alkene to alkane- H2 gas 150oc Ni catalyst
Alkene to alcohol- H2O H3PO4 steam
Alkene to haloalkane- electrophilic addition
Electrophile: an atom or group of atoms that is attracted to an electron
rich centre where it accepts a pair of electrons to form a new covalent
bond
The majority product is the one formed from the most stable carbocation-
attached to the most carbon atoms
Addition polymerisation- the formation of a very long molecular chain
by repeated additions of unsaturated alkene monomers
Combusted for energy generation, landfill, stored and recycled
Atom economy= total Mr of useful product/total Mr of all reactants
Percentage yield= actual mass/ theoretical mass
Haloalkanes
Haloalkanes have permanent dipole-dipole forces- stronger than alkanes-
weaker than alcohols since they have hydrogen bonds
Hydrolysis- a chemical reaction involving H20 that causes the breaking of
a bond in a molecule
Heating under reflux: the continual boiling and condensing of a reaction
mixture to ensure that the reaction takes place without the contents
boiling dry
Haloalkane to alcohol: nucleophilic substitution NaOH
Nucleophile: an atom or group of atoms that is attracted to an electron
deficient centre where it donates a lone pair of electrons to form a new
covalent bond
Ozone:
