Question

For the hydrolysis of ATP to ADP + Pi, the free-energy change is 7.3 kcal/mol under standard conditions (1 M concentration of both reactants and products). In the cellular environment, however, the free-energy change is about 13 kcal/mol. What can we conclude about the free-energy change for the formation of ATP from ADP and i under cellular conditions?

Answer 1

The correct answer will be- the free energy change will be +13 kcal/mol.

Step-by-step explanation:

The free energy change of a chemical reaction is the measure of the spontaneity of the reaction in which the negative value of free energy represents that reaction is exergonic while positive value represents that reaction is endergonic.

In the given question, if the free-energy change is 13 kcal/mol for the hydrolysis of ATP to ADP + Pi which releases energy used by the cells then reversal of the reaction that is the formation of ATP molecules from the ADP and Pi requires energy which will be the same energy required to break the ATP.

This shows that 13kcal/mol energy will be used but with a positive sign as the energy is needed or the reaction is endergonic.