Write : (a) molecular formula, (b) electron dot formula and (c) structural formula of ethene (ethylene).

The molecules of alkene family are represented by a general formula ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}}$. Answer the following:

(a) What do n and 2n signify ?

(b) What is the name of alkene when n = 4 ?

(c) What is the molecular formula of alkene when n=4?

(d) What is the molecular formula of the alkene if there are ten H atoms in it ?

(e) What is the structural formula of the third member of the alkene family ?

(f) Write the molecular formula of lower and higher homologous of an alkene which contains four carbon atoms.