Which reaction type is also known as "endergonic"?

The term "endergonic" is associated with reactions that absorb energy from their surroundings. Specifically, in thermodynamics, an endergonic reaction is one that requires an input of energy to proceed, which is indicative of a non-spontaneous reaction.

In this context, a non-spontaneous reaction is characterized by having a positive change in Gibbs free energy (ΔG > 0), meaning that the reaction will not occur on its own without the addition of energy. This is in contrast to spontaneous reactions, which occur naturally and have a negative change in Gibbs free energy (ΔG < 0).

Recognizing that exothermic reactions release energy rather than absorb it helps to clarify the distinction. While an exothermic reaction is always spontaneous, an endergonic reaction reflects a different scenario focused on the energy requirements rather than just heat release. Equilibrium reactions indicate a state where both forward and reverse reactions occur at equal rates, and they are not strictly categorized as endergonic or exergonic without further context.

Thus, describing endergonic reactions in the context of non-spontaneity highlights the essential link between the energy profile of these reactions and their likelihood to proceed without external energy.