C2H6\mathrm{C}_{2} \mathrm{H}_{6}C2H6
C2H5OH\mathrm{C_2H}_{5} \mathrm{OH}C2H5OH
CH3−O−CH3\mathrm{CH}_{3}-\mathrm{O}-\mathrm{CH}_{3}CH3−O−CH3
CH3OH\mathrm{CH}_{3} \mathrm{OH}CH3OH