Question

If a rocket runs on a fuel $\left( C _{15} H _{30}\right)$ and liquid oxygen, the weight of oxygen required and $CO _{2}$ released for every litre of fuel respectively are: (Given: density of the fuel is $0.756\, g / mL$ )

• A. $1188 \,g$ and $1296 \,g$
• B. $2376\, g$ and $2592 \,g$
• C. $2592\, g$ and $2376\, g$
• D. $3429 \,g$ and $3142\, g$

Answer 1

Answer: (C)

$C _{15} H _{30}+\frac{45}{2} O _{2} \rightarrow 15 CO _{2}+15 H _{2} O$
Mass of fuel $=0.756 \times 1000 \,g$
No. of moles of fuel $=\frac{0.756 \times 1000}{210}$
Wt. of oxygen $=\frac{0.756 \times 1000}{210} \times \frac{45}{2} \times 32=2592\, g$
Wt of $CO _{2}=\frac{0.756 \times 1000}{210} \times 15 \times 44=2376\, g$