To
determine the empirical formula of the compound given, we need to
determine the ratio of the elements present in the compound. To do that we use the given amount of sample
of the compound and the masses of each of the element included. Then, we calculate for the number
of moles of each element. We do as follows:
mass moles
Potassium 5.81 0.1486
Chlorine 5.27 0.1487
Oxygen 18.21 - 5.81 - 5.27 = 7.13 0.4456
Dividing the number of moles of each element with
the smallest value of number of moles, we will have the ratio of the elements:
K = 1 Cl = 1 O = 3
Therefore, the empirical formula would be KClO3.
