Question

When a certain amount of ethylene was burnt, 622 kJ heat was evolved. If heat of combustion of ethylene is 1411 kJ, the volume of $O_2$ that entered into the reaction is:

• A. $296.5$ mL
• B. $29.62$ L
• C. $6226$ $\times$ $22.4$ L
• D. $22.4$ mL

Answer 1

Answer: (B)

$29.62$ L

Oxidation of ethylene:

$C_2{H}_4+3O_2\to 2C{O}_2+2H_{2}O$

$\Delta H=1411KJ$ for 1 mole of ethylene.

Amount of $C_2{H}_4=\frac{622}{1411}$ moles
Volume of $O_2=3\times \frac{622}{1411}\times 22.4$ litre $=$ 29.62 litre