In an unknown liquid, the percentage composition with respect to carbon, hydrogen and iodine is 34.31%, 5.28% and 60.41% respectively.
Let the mass of liquid be 100 g thus, mass of carbon, hydrogen and oxygen will be 34.31 g, 5.28 g and 60.41 g respectively.
To calculate molecular formula of compound, convert mass into number of moles as follows:

Molar mass of carbon, hydrogen and iodine is 12 g/mol, 1 g/mol and 126.90 g/mol.
Taking the ratio:

Putting the values,

Thus, molecular formula of compound will be
.
The molecular formula of quinine is C20H<span>24N2</span>O<span>2. For every 1 mole of quinine molecule, there are 20 moles of carbon. Simply multiplying 6.0 moles by 20, we get, 120 moles.
Therefore, there are 120 moles of carbon in 6.0 moles of quinine.</span>
N=3^K-1 I really don't know how to explain it but that's the formula <span />
Substitution because you switch some of the other atoms when you get to the other side