Question

Problem 1: Electrochemistry in your body Living organisms derive energy from the oxidation of food, typified by glucose. C6H12O6(aq) + 6 O2(g) → 6 CO2(g) + 6 H2O(l) Electrons in this redox reaction are transferred from glucose to oxygen in a series of at least 25 steps. Here we calculate the total daily current flow in a typical organism and the rate of energy expenditure (power).

1.1) The molar enthalpy of combustion of glucose is -2,800 kJ/mol. If you are on a daily diet of 2,400 Cal (kilocalories), what amount of glucose (in moles and in grams) must be consumed if glucose is the only source of energy? What amount of oxygen (liters) is consumed in the oxidation process?

1.2) How many moles of electrons must be supplied to reduce the amount of O2 calculated in 1.1?

1.3) Using the result of 1.2 calculate the current (ampere) flowing in your body from the combustion of glucose.

1.4) Using the table of ΔGf below determine the equilibrium constant for the reaction, the standard cell potential and from this number estimate the rate of energy expenditure (= power) in Watts. ΔGf [kJ/mol] Glucose (s) -911 O2 (g) 0 CO2 (g) -394 H2O (l) -237

Answer 1