A compound has the following percentage composition by mass-
Carbon-14.4%
Hydrogen-1.2%
Chlorine-85.5%
The relative molecular mass of this compound is 168.50 what ia is molecular formula?
Element | Percentage composition | Atomic weight | Relative No. of atoms | Simplest ratio |
Carbon | 14.4 | 12 | 14.4/12 = 1.2 | 1.2/1.2 = 1 |
Hydrogen | 1.2 | 1 | 1.2/1 = 1.2 | 1.2/1.2 = 1 |
Chlorine | 84.5 | 35.5 | 84.5/35.5 = 2.38 | 2.38/1.2 = 2 |
Hence empirical formula is CHCl2.
n = Molecular mass/Empirical formula mass
= 168/(12 + 1 + 70)
= 168/83
= 2.
Therefore, molecular formula = (CHCl2)2 = C2H2Cl4.