What is the value of δg°' (or, to put it another way, the cost) when 2nadp+ and 2h2o are converted to 2nadph plus 2h+ plus o2?

The chemical reaction is given as:

Here, oxygen is oxidised and is reduced. Thus, redox reaction occurs.

For cell reaction,          (2)

where, = standard state free energy

n= number of electrons

F= Faraday constant ()

= cell potential

Substitute the value of number of electrons i.e. 2, Faraday constant and cell potential in the formula to determine the value of  .

Now, calculate the value of cell potential

          (1)

= (standard reduction potential of )

= (standard reduction potential of )

Put the above values in formula (1), we get:

=

Now, substitute above value in formula (2)

=

Since, one coulomb volt is equal to one joule.

Thus, value of is equal to or

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