Question: > 500 ml of a hydrocarbon gas burnt in excess of oxygen yields 2500 ml of CO2 and 3 lts of water vap...

Question

500 ml of a hydrocarbon gas burnt in excess of oxygen yields 2500 ml of CO2 and 3 lts of water vapours. All volume being measured at the same temperature and pressure. The formula of the hydrocarbon is

Answer 1

Solution

(2)

CxHy + O2 $\longrightarrow$ CO2 + H2O

$x \times n_{Cx}H_{y} = n_{CO_{2}}$ (POAC on C)

x ´ 500 = 2500 (x = 5)

y ´ nCx Hy = 2 ´ $n_{H_{2}O}$

(POAC on H)

y ´ 500 = 2 ´ 3000 y = 12

Formula = C5H12