Question

11. A compound contains 4.07 % hydrogen, 24.27% carbon and 71.65 % chlorine.
Its molar mass is 98.96 g. What are its empirical and molecular formula? (C2H4C12]​

Answer 1

Answer:

In 100g of sample of the compound, 4.07g of hydrogen, 24.27g of carbon and 71.65g of chlorine are present. Moles of hydrogen= 4.07g/ 1g = 4.0  Moles of carbon= 24.27g/ 12g = 2.0  Moles of chlorine= 71.65g/ 35g= 2.0  Since 2.0 is the smallest value, so by dividing each of the mole values obtained by this smallest value we will get a ratio of 2:1:1 for H:C:Cl.   Thus, the empirical formula of the compound is CH2Cl.  For CH2Cl, empirical formula mass= 12+ (2×1) +35 = 49g.  Molar mass/ empirical formula = 98.96g/ 49g = 2=n  Therefore, Empirical formula = CH2Cl  n=2  Hence, molecular formula= C2H4Cl2.