S-Cool Revision Summary

S-Cool Revision Summary

Aromatic compounds

The benzene ring is a regular hexagon of carbon atoms joined by six pi bonds. Six pi electrons are delocalised in an orbital above and below the ring.

Arenes react by electrophilic substitution where an electrophile is substituted for a hydrogen atom, which is lost as a proton.

An arene is chlorinated or brominated by the reaction between chlorine and bromine and the arene in the presence of iron (III) chloride or aluminium chloride.

A nitrating mixture consists of concentrated sulphuric acid and concentrated nitric acid, and produces NO2+ that can react with arenes to form nitroarenes.

Phenol and phenylamine have highly activated benzene rings and form trisubstituted substitution products at positions 2, 4 and 6 with electrophiles.

Methylbenzene reacts faster than benzene towards electrophilic reagents and forms substitution products at position 2, 4 and 6.

Alkenes are monomers that form addition polymerisation. Addition occurs due to the cleaving of the carbon double bond.

If ethene is the monomer the polymer made is polyethene.

In condensation polymerisation the addition of two monomers releases a small molecule, usually water.

In the formation of polyester the two polymers used are ethane 1,2-diol and benzene 1,4 dicarboxylic acid.When these add, an ester link is formed and water is released.

Polypeptides and proteins consist of long chains of amino acids.

Polypeptides are formed by a condensation polymerisation reaction between two amino acids.