H = 0.70 – 0.60 = 0.1 g

Element | % composition | At. wt. | Relative no. of atoms | Simplest ratio |
---|---|---|---|---|

Carbon | (0.60/0.70) × 100 = 85.71 | 12 | 85.71/12 = 7.142 | 7.142/7.142 = 1 |

Hydrogen | (0.1/0.70) × 100 = 14.28 | 1 | 14.28/1 = 14.28 | 14.28/7.142 = 2 |

Simplest ratio of whole numbers = C : H = 1 : 2

Hence, **empirical formula is CH _{2}**

Empirical formula weight = 12 + 2(1) = 14

Molecular weight = 70

n = Molecular\ weight\over Emperical\ Formula\ Weight

= 70\over 14 = 5

Molecular formula = (CH_{2})_{5} = C_{5}H_{10}

Hence, **Molecular formula = C _{5}H_{10}**