91Ó°ÊÓ

During normal breathing, humans exchange about \(0.5 \mathrm{~L}\) of air in their lungs. Calculate the amount of worked that is performed during one exhalation against atmospheric pressure. How many grams of ATP need to be hydrolyzed for breathing during a day (30 breath cycles per minute, \(\Delta G^{0^{\prime}}\) (ATP hydrolysis) \(=-31 \mathrm{~kJ} \mathrm{~mol}^{-1}, \mathrm{M}=507.18 \mathrm{~g} \mathrm{~mol}^{-1}\) ). A \(100 \mathrm{~g}\) bar of chocolate provides about \(500 \mathrm{~kJ}\) of energy. How long does the energy last just for breathing?

The enthalpy change for the reaction of glucose \(\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)\) to \(\mathrm{CO}_{2}\) and \(\mathrm{H}_{2} \mathrm{O}\) is \(-2800 \mathrm{~kJ}\) \(\mathrm{mol}^{-1}\), for the reaction of ethanol to water it is \(-1370 \mathrm{~kJ} \mathrm{~mol}^{-1}\). What is the enthalpy change during fermentation of glucose to ethanol? Is fermentation a useful metabolic pathway?

Calculate the change in entropy for the conversion of \(1 \mathrm{~mol}\) ice \(\left(\mathrm{H}_{2} \mathrm{O}(\mathrm{s}), 0^{\circ} \mathrm{C}\right)\) into vapor \(\left(\mathrm{H}_{2} \mathrm{O}(\mathrm{g}), 100^{\circ} \mathrm{C}\right)\) at constant pressure. Sublimation enthalpy \(\Delta H_{\text {subl }}=47 \mathrm{~kJ} \mathrm{~mol}^{-1}\), vaporization enthalpy \(\Delta H_{\text {vap }}=41 \mathrm{~kJ} \mathrm{~mol}^{-1}, C_{\mathrm{p}}=75 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1} .\)