- To find the percentage of composition of a substance means to find the percentage of mass of each element in the molecule of the substance to the mass of the molecule.
- The percentage of mass of an element can be determined by the following equation:
RAM = Relative atomic mass
RMM = Relative molecular mass
Calculate the percentage of composition of DDT (C14H9Cl5). [Relative atomic mass: Carbon = 14; Hydrogen = 1; Chlorine = 35.5]
Relative molecular mass of DDT