Polymerisation of ethylene

Polymerisation – many identical small molecules(monomers) combine into one large molecule(the polymer). Ethylene serves as a monomer from which polymers(polyethylene!) are made

(chemists are really lazy! the two lines on the left represent the double bond between the carbons(not shown) which then also have two assumed hydrogens each. on the right there is a carbon at each bend, again each with two assumed hydrogens, and 'arms' reaching out to the next ethylene monomer. the polymer is made of n monomer units.)