Question

Determine the mass of CO2 produced by burning enough of methane to produce 1.50×102kJ of heat. CH4(g)+2O2(g)→CO2(g)+2H2O(g)ΔH∘rxn=−802.3kJ Express your answer using three significant figures.

Answer 1

Answer: The mass of $CO_2$ produced will be 8.228 g.

Explanation:

We need to find the mass of carbon dioxide produced when 150 kJ of heat is released.

For the given chemical reaction:

$CH_4(g)+2O_2(g)\rightarrow CO_2(g)+2H_2O(g);\Delta H^o_{rxn}=-802.3kJ$

By Stoichiometry of the reaction:

802.3 kJ of energy is released when 1 mole of carbon dioxide is produced.

So, 150 kJ of energy will be release when = $\frac{1}{802.3}\times 150=0.187mol$ of carbon dioxide is produced.

To calculate the mass of carbon dioxide, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of carbon dioxide gas = 0.187 mol

Molar mass of carbon dioxide gas = 44 g/mol

Putting values in above equation, we get:

$0.187mol=\frac{\text{Mass of carbon dioxide gas}}{44g/mol}\\\\\text{Mass of carbon dioxide gas}=8.228g$

Hence, the mass of $CO_2$ produced will be 8.228 g.