Question

If a rocket runs on a fuel $\left(C_{15}{H}_{30}\right)$ and liquid oxygen, the weight of oxygen required and $C{O}_2$ released for every litre of fuel respectively are:

(Given : density of the fuel is 0.756 g/ mL)

Answer 1

$C_{15}{H}_{30}+\frac{45}{2}{O}_2\to 15C{O}_2+15H_{2}O$

One litre of fuel has a mass: $\left(0.756\right)\times 1000g$ = $756g$

$\therefore \text{Moles of}{C}_{15}{H}_{30}=\frac{756}{210}$

Moles of $O_2$ required $=\frac{45}{2}\times \frac{756}{210}$

Mass of $O_2$ required:
$=\frac{45}{2}\times \frac{756}{210}\times 32g=2592g$


Mass of $C{O}_2$ formed:
$=15\times \frac{756}{210}\times 44=2376g$