A chloride of silicon contains 79.1 mass % cl. (a) what is the empirical formula of the chloride?

An empirical formula is a formula that gives the proportions of the elements present in a certain compound however it does not give the actual numbers or the arrangement of the atoms. Assuming 100 grams of the compound, we determine the empirical formula as follows:

mass moles

Si 20.9 0.74404 0.74404/0.74404 = 1

Cl 79.1 2.23131 2.23131/0.74404 = 2.9989

Therefore, the empirical formula would be SiCl3.