Grams of Phosphorus = 4.14 grams Grams of white compound = 27.8 grams Grams of Chlorine would be = 27.8 - 4.14 = 23.66 grams Calculating moles which would be grams / molar mass Molar mass of P = 30.97 grams / moles; Molar mass of Cl = 35.45 grams / moles Moles of Phosphorus = 4.14 grams / 30.97 grams / moles = 0.1337 moles Moles of Chlorine = 23.66 grams / 35.45 grams / moles = 0.6674 moles Calculating the ratios by dividing with the small entity P = 0.1337 moles / 0.1337 moles = 1 Cl = 0.6674 moles / 0.1337 moles = 5 So the empirical formula would be PCl5
