(10) Which of the following statements about ATP is true? B.) C. D. the energy o
ID: 1087314 • Letter: #
Question
(10) Which of the following statements about ATP is true? B.) C. D. the energy of hydrolysis is the same for all of the phosphate groups of the molecule despite the very exergonic nature of the hydrolysis, ATP does not hydrolyze spontaneous due to a very high activation energy the G of hydrolysis within the cell is substantially greater than the Go, due to a higher concentration of ATP with respect to ADP electrostatic attraction of the phosphate groups contributes to a more exergonic free energy E. both B and C are corret 5. (10) The reduction of pyruvate to lactate has an.F of-0.185 V while the reduction of acetaldehyde to cthanol has an E of -0.197 V. If these two reactions are coupled to produce a spontancous reaction which of the following would be the reducing agent? Calculate the (for this reaction if two electrons are transferred, and Faraday's constant is 96,485 I/Vmol. C1 -Explanation / Answer
Pyruvate --------> Lactate; E0’ = -0.185 V
Acetaldehyde --------> Ethanol; E0’ = -0.197 V
The more negative the reduction potential of a system, the more difficult is it to reduce the system. Since acetaldehyde/ethanol has a more negative reduction potential, hence, it is comparatively difficult to reduce acetaldehyde to ethanol. Therefore, the reduction half consists of Pyruvate while the oxidation half contained Ethanol.
The half reactions are:
Oxidation: Ethanol --------> Acetaldehyde; E0’ox = -E0’ = -(-0.197 V) = 0.197 V
Reduction: Pyruvate ----------> Lactate; E0’red = -0.185 V
The redox reaction is
Ethanol + Pyruvate ---------> Acetaldehyde + Lactate; E0’cell = E0’red + E0’ox = -0.185 V + 0.197 V = 0.012 V.
Since ethanol is itself oxidized to acetaldehyde, ethanol is the reducing agent (ans).
Given, the number of electrons transferred n = 2 and Faraday’s constant, F = 96485 J.V-1mol-1, we use the relation
G0’ = -n*F*E0’cell = -(2)*(96485 J/V.mol)*(0.012 V) = -2315.64 J/mol = -(2315.64 J/mol)*(1 kJ/1000 J) = -2.31564 kJ/mol -2.315 kJ/mol (ans).
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.