In human cells, a compound known as [tex]\mathrm{NADH}[/tex] is involved in a reaction that generates an electrical potential. The reaction is based on the two half-reactions shown in the table above. The balanced equation for the overall reaction is shown below.
[tex]
\mathrm{O} 2+2 \mathrm{H}++2 \mathrm{NADH} \rightarrow 2 \mathrm{H} 2 \mathrm{O}+2 \mathrm{NAD}+
[/tex]
(a) How many moles of electrons are transferred for each mole of [tex]\mathrm{O} 2[/tex] that reacts? Justify your answer in terms of the balanced equation and the change in oxidation number of oxygen.
(b) Calculate the electrochemical potential of the overall reaction.
(c) Calculate the value of [tex]\Delta G^{\circ}[/tex] for the overall reaction.
(d) When the concentration of NADH increases while the concentration of NAD+ decreases, will the electrochemical potential increase, decrease, or remain the same? Justify your answer.