Question

Redox : If members of the redox couples above were used to set up the most energetically favorable chemical reaction, the initial electron donor should be ___and the final electron acceptor should be ___.

Use the information from the redox couples below to answer the fill in the blank questions, using the letter after each substance. (i.e. if you believe that the answer is CoQ fill in the appropriate blank with the letter A). Each letter (substance) may be used more than once. Hint: put the redox couples into an accurate electron tower first, based on their redox potentials. Redox Couples (potential in volts) CoQ (A)/CoQH2 (B) +0.10 V; Fe3+ (c)/Fe2 (D)- +0.771 V; SO42(E)/S°(F) -0.20 V NO2 (G)/NH4 (H) +0.44 V; CO2 (1)/glucose(U)--0.43 V; CO2(K)/CH4(L) 0.24 V NAD (M)/NADH(N)--0.32 V; H (O)/H2(P)--0.42V; O2 (Q)/H2O(R)- +0.815 V pyruvate(S)/lactate(T) 0.19 V; S°(U)/H2S(V)--0.27 V; NO3(W)/N2(X) +0.74 V.

Answer 1

If members of the given redox couples were chosen to make the most energetically favourable reaction, the intitial electron donor should be J and the final electron acceptor should be Q, as they have the highest difference in reduction potentials.