Gibbs free energy formula is.
Solution and Explanation
Gibbs free energy is equal to the enthalpy of the system less the product of the temperature and entropy.
The equation is given as:
\(G = H – TS\)
Where,
G = Gibbs free energy
H = enthalpy
T = temperature
S = entropy
OR or a more complete equation would be given as:
\(G = U + PV – TS\)
Where,
U = internal energy (SI unit: joule)
P = pressure (SI unit: pascal)
V = volume (SI unit: m3 )
T = temperature (SI unit: kelvin)
S = entropy (SI unit: joule/kelvin)
Gibbs free energy is also connected to the transformation in the overall entropy of the universe during a particular process at a given temperature. Precisely, the equation is as follows: ΔG = -TΔSuniv, where T denotes temperature, and ΔSuniv signifies the modification in the universe's entropy.
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Questions Asked in BITSAT exam
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Concepts Used:
Gibbs Free Energy
The energy associated with a chemical reaction that can be used to do work.It is the sum of its enthalpy plus the product of the temperature and the entropy (S) of the system.
The Gibbs free energy is the maximum amount of non-expansion work that can be extracted from a thermodynamically closed system. In completely reversible process maximum enthalpy can be obtained.
ΔG=ΔH−TΔS
The Conditions of Equilibrium
If both it’s intensive properties and extensive properties are constant then thermodynamic system is in equilibrium. Extensive properties imply the U, G, A.
