How much energy (in kJ) is available for sustaining muscular and nervous activity from the combustio — Thermodynamics and Thermochemistry Chemistry Question
Question
How much energy (in kJ) is available for sustaining muscular and nervous activity from the combustion of 1.0 mole of glucose molecules under standard conditions at $37^\circ\text{C}$ (body temperature)? The standard entropy and enthalpy of reaction are $+200\text{ J/K-mol}$ and $-2808\text{ kJ/mol}$, respectively.
💡 Solution & Explanation
The available energy for useful work strictly matches the magnitude of the Gibbs Free Energy change ($-\Delta G$). $\Delta G = \Delta H - T\Delta S = -2808\text{ kJ} - (310\text{ K} \times 0.200\text{ kJ/K}) = -2808 - 62 = -2870\text{ kJ}$. The available energy magnitude is $2870\text{ kJ}$.