H3C(CH2)5CH3\mathrm{H}_{3} \mathrm{C}\left(\mathrm{CH}_{2}\right)_{5} \mathrm{CH}_{3}H3C(CH2)5CH3
Pb(C2H5)4\mathrm{Pb}\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{4}Pb(C2H5)4
C4H8\mathrm{C}_{4} \mathrm{H}_{8}C4H8
None \text { None } None