Question

Given the values of ΔGfo given below in kJ/mol, calculate the value of ΔGo in kJ for the combustion of 1 mole of butane to form carbon dioxide and liquid water. ΔGfo (C4H10(g)) = -17 ΔGfo (CO2(g)) = -395 ΔGfo (H2O(l)) = -238

Answer 1

Answer:

Δ$_rG=-2753kJ$

Explanation:

Hello,

Butane's combustion is:

$C_4H_{10}+\frac{13}{2} O_2-->4CO_2+5H_2O$

Now the change in the Gibbs free energy for this reaction is computed via (don't forget that oxygen's Gibbs free energy of formation is 0 since it is an element):

Δ$_rG=$4Δ$_fG_{CO_2}+$5Δ$_fG_{H_2O}$-Δ$_fG_{C_4H_{10}}$

Δ$_rG=4(-395kJ/mol)+5(-238kJ/mol)-(-17kJ/mol)$

Δ$_rG=-2753kJ/mol$

Now, since the calculation is done for 1 mol of butane, the change in the Gibbs free energy for this fuel is:

Δ$_rG=-2753kJ$

Best regards.