Consider the following thermochemical reaction for kerosene: 2 C12H26(l) + 37 O2(g)  24 CO2(g) + 26 H2O(l) + 15,026 kJ

(a) When 21.3 g of CO2 are made, how much heat is released?

We have to solve this question using the stoichiometry of the reaction:

The equation of the reaction is;

According to the question;

Number of moles of CO2 released = 21.3 g/44 g/mol = 0.48 moles

From the  stoichiometry of the reaction:

Since;

24 moles of CO2 released 15,026 KJ

0.48 moles of CO2 will release 0.48 * 15,026/24

= 301 KJ of heat.