Question

The empirical formula of a hydrocarbon is found to be CH. Labratory procedures have found that the molar names of the combine is 78 g/mol. What is the molecular formula of this compound?

Answer 1

Answer:

                      Molecular Formula  =  C₆H₆

Explanation:

Molecular formula is calculated by using following formula,

                    Molecular Formula  =  n × Empirical Formula  ---- (1)

Also, n is given as,

                     n  =  Molecular Weight / Empirical Formula Weight

Molecular Weight  =  78.0 g.mol⁻¹

Empirical Formula Weight  =  12 (C) + 1 (H)  =  13 g.mol⁻¹

So,

                     n  =  78.0 g.mol⁻¹ ÷ 13 g.mol⁻¹

                     n  =  6

Putting Empirical Formula and value of "n" in equation 1,

                    Molecular Formula  = 6 × CH

                    Molecular Formula  =  C₆H₆