The sixth member of the class of the aliphatic alkanes is Hexane with the molecular formular C6_66H14_{14}14
Percentage by mass of Hydrogen = mass of Hydrogen in compoundTotal mass of compound\;\frac{\text{mass of Hydrogen in compound}}{\text{Total mass of compound}}Total mass of compoundmass of Hydrogen in compound×100\times 100×100
Total mass of compound, C6_66H14_{14}14 = (12 x 6) + (1 x14) = 72 + 14 = 86
Mass of Hydrogen in compound = 14(H) = 14×1\times 1×1 = 14
% mass of H = 1486\;\frac{14}{86}8614×100\times 100×100
= 16.28%
