Temperature Of Phase Change Calculation

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Changed: 1c1

One way of determining if a process/reaction is spontaneous in the direction we wrote/want, is to determine the entropy change of the universe, deltaS_univ.

One way of determining if a process/reaction is spontaneous in the direction we wrote/want, is to determine the entropy change of the universe, ΔS_univ.

Changed: 3c3

The equation is deltaS_univ = deltaS^o_sys + {(-deltaH^o_sys)/T_sys)}

The equation is Δ_univ = ΔS^o_sys + {(-ΔH^o_sys)/T_sys)}

Changed: 5,6c5,6

So you can start picking different temperatures (T_sys) and calculating what the deltaS_univ will be for that temperature. If you do this several time and pick the correct temperatures, you can see where the deltaS_univ does from positive to negative or visa versa. Whichever way, it is when

deltaS_univ=0 is where the system is at Equilibrium

So you can start picking different temperatures (T_sys) and calculating what the ΔS_univ will be for that temperature. If you do this several time and pick the correct temperatures, you can see where the ΔS_univ does from positive to negative or visa versa. Whichever way, it is when

ΔS_univ=0 is where the system is at Equilibrium

One way of determining if a process/reaction is spontaneous in the direction we wrote/want, is to determine the entropy change of the universe, ΔS_univ.
The equation is Δ_univ = ΔS^o_sys + {(-ΔH^o_sys)/T_sys)}
So you can start picking different temperatures (T_sys) and calculating what the ΔS_univ will be for that temperature. If you do this several time and pick the correct temperatures, you can see where the ΔS_univ does from positive to negative or visa versa. Whichever way, it is when

ΔS_univ=0 is where the system is at Equilibrium

This physically means that the system is going through a phase change and that system temperature is Temperature of Phase Change. For example, the boiling (condensation)point, melting freezing)point, etc.

Example : H₂O_(l)==> H₂O_(g)