3. Experimental Determination of AG for ATP Hydrolysis A direct measurement of the standard free- energy change associated with the hydrolysis of ATP is technically demanding because the minute amount of ATP remaining at equilibrium is difficult to measure accurately. The value of AGo can be calculated indirectly, however, from the equilibrium constants of two other enzymatic reactions having less favorable equilibrium constants: Glucose6-phosphate + HO - glucose + Pi Keg= 270 ATP + glucose > ADP + glucose6-phosphate Key 890 Using this information for equilibrium constants determined at 25 °C, calculate the standard free energy of hydrolysis of ATP.

3. Experimental Determination of AG for ATP Hydrolysis A direct measurement of the standard free- energy change associated with the hydrolysis of ATP is technically demanding because the minute amount of ATP remaining at equilibrium is difficult to measure accurately. The value of AGo can be calculated indirectly, however, from the equilibrium constants of two other enzymatic reactions having less favorable equilibrium constants: Glucose6-phosphate + HO - glucose + Pi Keg= 270 ATP + glucose > ADP + glucose6-phosphate Key 890 Using this information for equilibrium constants determined at 25 °C, calculate the standard free energy of hydrolysis of ATP.

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter17: Spontaneity, Entropy, And Free Energy

Section: Chapter Questions

Problem 23Q: Monochloroethane (C2H5Cl) can be produced by the direct reaction of ethane gas (C2H6) with chlorine...

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Glycolysis is the process by which glucose is metabolized to lactic acid according to the equation C6H12O6(aq)2C3H6O3(aq) G=198 kJ at pH 7.0 and 25°C Glycolysis is the source of energy in human red blood cells. In these cells, the concentration of glucose is 5.0103 M, while that of lactic acid is 2.9103 M. Calculate AG for glycolysis in human blood cells under these conditions. Use the equation G=G+RT In Q, where Q is the concentration quotient, analogous to K.
Monochloroethane (C2H5Cl) can be produced by the direct reaction of ethane gas (C2H6) with chlorine gas or by the reaction of ethylene gas (C2H4) with hydrogen chloride gas. The second reaction gives almost a 100% yield of pure C2H5Cl at a rapid rate without catalysis. The first method requires light as an energy source or the reaction would not occur. Yet G for the first reaction is considerably more negative than G for the second reaction. Explain how this can be so.
List two ways that enzyme catalysis of a reaction is superior to normal conditions.
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Calculate the equilibrium constant at 37oC for the reactionGlucose + 6O2 + 36ADP + 36Phospate → 6CO2+ 42H2O +36ATP ... ... ...Gibbs free energychange of Go= − 423 kcal/mole of Glucose
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