Page 39 - Biochemistry2 (08PB403)
P. 39
Free energy
• Neither ΔH nor ΔS by itself is sufficient to determine whether a
chemical reaction proceeds spontaneously in the direction it is
written.
• However, when combined together, enthalpy (ΔH) and entropy (ΔS)
can be used to define a third quantity, Gibbs free energy (or Gibbs
function) (ΔG).
• (ΔG) is the change in free energy, used as a tool to predict whether
the reaction is exergonic or endergonic.
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