Bond Formation and ATP

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Joshua Wiedner
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Bond Formation and ATP

Postby Joshua Wiedner » Fri Jan 08, 2016 7:57 pm

In chemistry I learned that bond breaking is an endothermic process that uses energy and that bond formation is an exothermic process that releases energy. However in previous introductory biology classes I had learned that Breaking the ATP bonds releases energy. How can the breaking of a bond which is endothermic for ATP release energy?

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Re: Bond Formation and ATP

Postby Chem_Mod » Fri Jan 08, 2016 9:24 pm

Very good question! Breaking a bond is surely an endothermic process. However, in the ATP case, we are talking about a reaction ATP -> ADP + Pi. Delta H (rxn) = H (products) - H (reactants). In this case it ends up to be exothermic. Even though this process is not forming any bond, the enthalpy of the products are still lower than the reactants which makes it an exothermic process.

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