Calculate the Standard Potential for the Oxidation of Malate by NAD+

What is the standard potential for the oxidation of malate by NAD+?

Malate + NAD+ → Oxaloacetate + NADH + H+

a) -4.81 V

b) +4.81 V

c) -0.149 V

d) +0.149 V

e) +0.0523 V

Answer:

The standard potential for the oxidation of malate by NAD+ is 0.149 V. The correct answer is c) -0.149 V.

The standard reduction potential is a measure of the tendency of a species to be reduced or oxidized. In the given reaction, malate is being oxidized to form oxaloacetate, while NAD+ is being reduced to form NADH.

To calculate the standard potential, we can use the formula:

ΔEº = Eº(acceptor) - Eº(donor)

Given that the standard reduction potential of oxaloacetate (acceptor) is -0.166 V and the standard reduction potential of NAD+ (donor) is -0.315 V, we can substitute these values into the formula:

ΔEº = -0.166 V - (-0.315 V)

ΔEº = -0.166 V + 0.315 V

ΔEº = 0.149 V

The standard potential for the oxidation of malate by NAD+ is 0.149 V.