Question

A gaseous hydrocarbon occupying 2.24 at ntp produces 4.4 grams of CO2 and 3.6 grams of H2O calculate the empirical formula of hydrocarbon

Answer 1

Hydrocarbon → CO₂ + H₂O

At NTP, 1 mole of any gas occupies 22.4 litres

so 2.24 litres is occupied by 0.1 moles

Number of moles of CO₂= given mass/gram molecular mass

= 4.4/44 = 0.1 moles

Number of moles of H₂O = given mass/gram molecular mass

= 3.6/18 = 0.2 moles

So, 0.1 moles of Hydrocarbon decomposes to give 0.1 moles of CO₂ and 0.2 moles of H₂O

Simplifying, we may write 1 mole of Hydrocarbon decomposes to give 1 mole of CO₂ and 2 moles of H₂O

So, a balanced chemical equation is written as

CH₄ + 2 O₂ → CO₂ + 2 H₂O

Thus, the Empirical formula of the hydrocarbon is CH₄

Hope it helps!!