Calculate the mass of CO2 produced by thecombustion of a tank of gasoline. Assume themass of a tank of gasoline is 46.0 kg and thatgasoline is pure octane (C8H18).

2 Answers

jeew-m's profile pic

jeew-m | College Teacher | (Level 1) Educator Emeritus

Posted on

`C_8H_18+27/2O_2 rarr 8CO_2+9H_2O`


When you have a combustion of hydrocarbon as results we will get `CO_2` and water.

Mole mass

`C_8H_18 = 114g/(mol)`

`CO_2 = 44g/(mol)`


Amount of `C_H_18` reacted `= 46kg`

Amount of `C_H_18` reacted `= 46000/114 mol`


Mole ratio

`C_8H_18:CO_2 = 1:8`


Amount of` CO_2` formed `= 46000/114xx8 moles`

Amount of `CO_2` formed `= 46000/114xx8xx44 g`

Amount of `CO_2` formed `= 142035g`


So 142.035kg of `CO_2` will be formed.


llltkl's profile pic

llltkl | College Teacher | (Level 3) Valedictorian

Posted on

Assuming complete combustion (in sufficient supply of oxygen or air), the balanced chemical equation for the combustion of pure octane (C8H18) is,

2C8H18 + 25O2 = 16CO2 + 18H2O

The stoichiometry of this reaction shows that, 2 moles of the gasoline upon combustion produces 16 moles of CO2

Or, 2× (8×12+18×1) i.e. 228 gm gasoline upon combustion produces 16*44 gms = 704 gms of CO2.

Then, 46 kg, i.e. 46000 gms gasoline should produce 704*46000/228 = 142035.1 gms = 313.134 lbs of CO2 on complete burning.

Hence, 313.13 lbs of CO2 will be formed on burning 46 kg of that gasoline.