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Physical significance of four thermodynamic formula
This is the most basic thermodynamic formula, which has no physical meaning and is a pure differential equation. But these four equations can be deduced.

There are many equations used to derive these four equations, but they have great physical significance. If you are a high school student, I suggest you recite these four formulas. If you are a college student, I can give you a detailed derivation process.

I just finished my sophomore year. . . I'm so sorry, teach fish to swim.

Definition of entropy

dS=dQ/T

first law of thermodynamics

dU=dQ+dW

Volume change work

dW=-pdV

therefore

dS=(dU+pdV)/T

That is dU=TdS-pdV.

Definition of enthalpy

H=U+pV

distinguish

dH=dU+pdV+Vdp

Bring dU=TdS-pdV and get

dH=TdS+Vdp

Definition of free energy

F=U-TS

difference

dF=dU-TdS-SdT

Bring it in with dU=TdS-pdV, and get

dF=-SdT-pdV

Definition of Gibbs function

G=U-TS+pV

The same difference

dG=dU-TdS-SdT+pdV+Vdp

Bring it in with dU=TdS-pdV, and get

dG=-SdT+VdP

This is the derivation of four formulas, which are generally used to derive Maxwell relations, that is, the relationship between the partial derivatives of four variables S, T, P and V. Maxwell relations are only used to push some messy things, and I have learned a little, so these formulas seem to me to be the time to prove some equations and various substitutions repeatedly, which is very annoying.