Summary Δ Calculations Simplified: Thermodynamics & Reaction Energy

In
biochemistry , delta (1) calculations used to denote changes are

in a given quantity , such free energy , enthalpy , entropy as or .




These calculations help determine the direction, Spontaneity , and
energetics of biochemical reactions and
processes.

Common delta calculations


① AG (Gibbs Free
Energy Change
Represents the change in
free energy during a reaction.

·


Calculation :
AG =
AH-TAS , where :


AH :

change in enthalpy (heat energy
T:
temperature in Kelvin

AS change in
entropy (disorder
:




Interpretation :




D1G40 : The reaction is spontaneous (exerqonid
If AG XO The reaction non- spontaneous (endergonia
:
is



D1G = 0 :
The reaction is at
equilibrium .




② SH (Enthalpy change)
The
change in heat content or
enthalpy of a reaction .




Interpretation :




19SH(0 : The reaction is exothermic (releases heat

The (absorbs heat)
If AHSO reaction is endothermic
:




③ AS (Entropy change
IS
represents the
change in
entropy ,
or the degree of disorder
in a
system .




Interpretation :




DASSO :
The system's disorder increases .




191S4O :
The system's disorder decreases.