Answer:
31.3 kJ/mol is the free energy, ΔG, for the overall reaction, A⇌D.
Explanation:
A⇌B, [tex]\Delta G_1[/tex] = 11.9 kJ/mol ...[1]
B⇌C, [tex]\Delta G_2[/tex]= -26.7 kJ/mol ...[2]
C⇌D, [tex]\Delta G_3[/tex]= 7.30 kJ/mol ...[3]
A⇌D, [tex]\Delta G_4[/tex] = ?...[4]
[4] = [1] - [2] - [3] (Using Hess's law)
[tex]\Delta G_4=\Delta G_1-(\Delta G_2+\Delta G_3)[/tex]
[tex]=11.9 kJ/mol - (-26.7 kJ/mol+7.30 kJ/mol)[/tex]
[tex]=\Delta G_4=31.3 kJ/mol[/tex]
31.3 kJ/mol is the free energy, ΔG, for the overall reaction, A⇌D.