The key step in the metabolism of glucose for energy is the isomerization of glucose−6−phosphate (G6P) to fructose−6−phosphate (F6P): G6P ⇌ F6P K = 0.510, at 298K. A. Calculate ΔG when Q, the [F6P]/[G6P] ratio, equals 10.0.B. Calculate ΔG when Q = 0.100.C. Calculate Q if ΔG = 2.50 kj/mol.

Answer :

(A) The value of is, 7.37 kJ/mol

(B) The value of is, -4.03 kJ/mol

(C) The value of Q for the reaction is, 1.39

Explanation :

The given balanced chemical reaction is,

The expression for reaction quotient will be :

Given:

k = 0.510

First we have to calculate the for the reaction.

Part A:

Now we have to calculate the value of .

The formula used for is:

   ............(1)

where,

= Gibbs free energy for the reaction  = ?

=  standard Gibbs free energy  = 1.67 kJ/mol

R = gas constant =

T = temperature = 298 K

Q = reaction quotient = 10.0

Now put all the given values in the above formula 1, we get:

Thus, the value of is, 7.37 kJ/mol

Part B:

Now we have to calculate the value of .

The formula used for is:

   ............(1)

where,

= Gibbs free energy for the reaction  = ?

=  standard Gibbs free energy  = 1.67 kJ/mol

R = gas constant =

T = temperature = 298 K

Q = reaction quotient = 0.100

Now put all the given values in the above formula 1, we get:

Thus, the value of is, -4.03 kJ/mol

Part C:

Now we have to calculate the value of Q.

The formula used for is:

   ............(1)

where,

= Gibbs free energy for the reaction  = 2.50 kJ/mol

=  standard Gibbs free energy  = 1.67 kJ/mol

R = gas constant =

T = temperature = 298 K

Q = reaction quotient = ?

Now put all the given values in the above formula 1, we get:

Thus, the value of Q for the reaction is, 1.39