PART A: Use the following glycolytic reaction to answer the question. If the concentration of DHAP is 0.125 M and the concentrat

Question

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PART A: Use the following glycolytic reaction to answer the question. If the concentration of DHAP is 0.125 M and the concentrat

ion of G3P is 0.06 M in a cell, what is the free energy change (ΔG)? Give your answer in 3 significant figures. (NOTE: Units are asked for in Part B.)
DHAP -> G3P (reversible)

Keq=5.4e-2
PART B: Units are important for all mathematical calculations. What are the units for free energy change in Part A?
PART C: Select ALL answers that correctly complete this sentence. Based on the calculated free energy change in Part A, the

a) forward reaction is favorable
b)forward reaction is unfavorable
c) reverse reaction is favorable
d) reverse reaction is unfavorable.

Chemistry

1 answer:

alisha [2.9K] · Answer 1 · 2026-03-09T09:40:28+03:00

Answer:

For A: The change in free energy for the reaction is -5339.76 J/mol

For B: Free energy change is expressed in kJ/mol

For C: The forward reaction favors progression, while the reverse reaction does not.

Explanation:

Regarding the specified chemical reaction:

$DHAP\rightleftharpoons G_3P$

For A:

The relationship between standard Gibbs free energy and equilibrium constant is as follows:

$\Delta G^o=-RT\ln K_{eq}$

The free energy change can be calculated using the following equation:

$\Delta G=\Delta G^o+RT\ln Q$

Or,

$\Delta G=-RT^o\ln K_{eq}+RT\ln Q$

where,

$\Delta G$ = Change in free energy

R = Gas constant = $8.314J/K mol$

$T^o$ = standard temperature = $25^oC=[273+25]K=298K$

T = temperature of the cell = $37^oC=[273+37]K=310K$

$K_[eq}$ = equilibrium constant = $5.4\times 10^{-2}$

Q = reaction quotient = $\frac{[G_3P]}{[DHAP]}$

$[G_3P]$ = 0.06 M

[DHAP] = 0.125 M

Substituting the values into the equation yields:

$\Delta G=[-(8.314J/mol.K\times 298K\times \ln (5.4\times 10^{-2}))]+[(8.314J/mol.K\times 310K\times \ln (\frac{0.06}{0.125}))]\\\\\Delta G=-[-7231.46]+[-1891.7]=-5339.76J/mol$

Thus, the change in free energy for the reaction is -5339.76 J/mol

For B:

To convert the free energy change to kilojoules, we apply the conversion factor:

1 kJ = 1000 J

So, $-5339.76J/mol\times \frac{1kJ}{1000J}=-5.34kJ/mol$

Consequently, the free energy change's units are kJ/mol

For C:

For spontaneity in the reaction, the Gibbs free energy must be negative. However, the calculations indicate a positive Gibbs free energy, leading to the conclusion that the reaction is not spontaneous.

The free energy change of the reaction is negative.

Consequently, the forward reaction is favored and the reverse reaction is not favored.