Hydrogen peroxide has the empirical formula HO and an empirical formula weight of 17.0 amu. If the molecular weight is 34.0 amu, what is the molecular formula?

1 Answer
Oct 1, 2016



First, you want to find the ratio between the empirical formula and molecular formula; that is, how much has the molecular formula been simplified to reach the empirical formula. We do this by dividing the molecular weight by the empirical weight.

#34.0/17.0# = 2

Therefore, the molecular formula has been halved in order to obtain the empirical formula. Now multiple the empirical formula by 2 to obtain the molecular formula.

HO x 2 = #H_2##O_2#