CH3COOC2H5\mathrm{CH}_{3} \mathrm{COOC}_{2} \mathrm{H}_{5}CH3COOC2H5
C2H4\mathrm{C}_{2} \mathrm{H}_{4}C2H4
CH3CH2OH\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}CH3CH2OH
C2H6\mathrm{C}_{2} \mathrm{H}_{6}C2H6