ATP → ADP + Pi   (ΔG°’ = -30.5 kJ/mol) In cells, the [ATP] is 0.5 mM, the [ADP] is 4.5 mM, and the [Pi] is 0.65 mM. Calculate the free energy change for ATP hydrolysis under cellular conditions. Enter the numerical value in units of kJ/mol and round to the nearest tenths place.

a) As stated in question 5a, glucose (C6H12O6(s)) is a source of cellular energy. Calculate the standard free energy for the metabolism of glucose: Given ΔG°C6H12O6(s) =  -911kJ/mol; ΔG°O2(g) = 0kJ/mol; ΔG°CO2 = -394kJ/mol; ΔG°H2O(l) = -237kJ/molC6H12O6(s) + 6O2(g) ➝ 6CO2(g) + 6H2O(l)  b) Cells couple the hydrolysis of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) andinorganic phosphate (PO43–) to drive chemical reactions (i.e. as a source of chemical energy). The reaction is: ATP(aq) + H2O(l) ➝ ADP(aq) + PO43–(aq) Calculate K for this reaction if ΔG° = –30.5 kJ/mole. c) If all of the energy from glucose metabolism went into ATP synthesis from ADP and inorganicphosphate, how many molecules of ATP could be generated from each molecule of glucose?

Actual free-energy change is a function of the reactant and product concentrations and the temperature at which the reaction occurs. AG = Go + RT In Use the equation for the actual free-energy change to plot AG against In Q at 25 °C for the five concentrations of ATP, ADP, and P₁ shown in the table. The AG' for the reaction is -30.5 kJ/mol. Concentration (mm) 0.2 5.0 14.9 O O AG (kJ/mol) Metabolite ATP ADP P₁ Select the graph that plots the data. AG (kJ/mol) 0 -20 -40 -~ 0 200 0 -200 [C]c[D]d [A]a[B]b -400 T 2 5 0.2 10 2 T 4 3 2.2 12.1 InQ 6 4 InQ 6 8 1 4.2 14.1 10 8 5 25 10 AG (kJ/mol) AG (kJ/mol) 0 -20 -40 -10 -8 0 -20 -40 -6 -4 InQ -2 0

Calculate ΔG° for the following reactions at 25°C using the standard free energies of formation of the reactants and products.Compound ΔGof (kJmol)ΔGfo(kJmol)    The equation H2O(l) → H2O(g)  ΔGoΔGokJ C2H2(g)209.9 CO2(g)-394.4 H2O(g)-228.6 H2O(l)-237.1 N2(g)0 NO(g)87.6 O2(g)0

The standard reaction free energy N2(g) + 3H2(g) 2 NH3(g) AGº =-34. kJ for this reaction: Use this information to complete the table below. Round each of your answers to the nearest kJ. reaction 6NH3 (g) 3N2(g) + 9H₂ (g) AGº kJ - 2NH3(g) N2(g) + 3H2(g) ☐ kJ 2N2 (g) + 6H₂ (g) → 4NH3 (g) ☐ kJ ☐ x10 ☑

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The standard free energy change for the hydrolysis of ATP is -30.5 kJ ATP(aq)+H₂O(1)→ADP(aq) +Pi(aq) In a particular cell, the concentrations of ATP, ADP, and Pi are 0.0031 M, 0.0015 M, and 0.0048 M, respectively. Calculate the free energy change for the hydrolysis of ATP under these conditions. (Assume a temperature of 298 K.)