Gibbs free energy Calculator calculates the Gibbs free energy (G), enthalpy (H), Helmoltz free energy (A) and internal energy of the system (U) if any of the three quantities are given.
Read the given problem and observe the given quantities.
Step 2 :
Use the Gibbs free energy formula:
G = H + A - U
where G = Gibbs free energy,
H = Enthalpy,
A = Helmotz free energy and
U = Internal energy of the system.
Substituting the given values in the formula, we get the answer.
Calculate the Gibbs free energy of the following reaction:
C6H12O6 + 6O2 ----> 6CO2(g) + 6H2O(g)
If Enthalpy is - 2540 KJ, Helmoltz free energy A is 1000 J and Internal energy is 20 J.
Step 1 :Given: Enthalpy H = - 2540 KJ,
Helmoltz free energy A = 1000 J,
Internal energy U = 20 J
Step 2 :G = H + A - U
= - 2540 $\times$ 103 + 1000 - 20
= - 2539 KJ.
Answer :The Gibbs free energy is - 2539 KJ.
Find the Helmoltz free energy of the reaction:
4 NH3 + OH --> HNO3 + OH.
If Enthalpy is - 21.3 J, Gibbs free energy is - 35 J and Internal energy is 10 J.
Step 1 :Given: Enthalpy H = - 21.3 J,
Gibbs free energy G = - 35 J,
Internal energy U = 10 J
Helmoltz free energy A = ?
Step 2 :G = H + A - U
=> A = G - H + U
= - 35 - (- 21.98) + 10
= - 3.08 J.
Answer :The Helmoltz free energy A is - 3.08 J.