Entropy related to Enthalpy

[Joshua Eidam 2A]

In outline 4, there is a bullet saying we should know how to "show how ∆S is related to ∆H for a change at constant temperature and pressure and explain the
relationship". I am confused as to which equation this is referring to and wanted to make sure I understand the right connection I should be making in terms of entropy and enthalpy?

[Katie Nye 2F]

That is Gibbs free energy equation! It is applicable at constant temperature and pressure. deltaG = deltaH - TdeltaS

[Charlie Russell 2L]

Yeah, Gibbs Free Energy! It's in Lecture 16, I believe!

[Lisa Seidl 3H]

Another thing to keep in mind is that for the Gibbs Free Energy equation, the T must be a constant temperature and make sure your G, S, and H values are all in either kJ or J and your T is in Kelvin.

[Justin Nguyen 3E]

You can also represent the relationship between entropy and enthalpy using the formula ΔS = ΔH/T at temperature T. ΔH would usually be q, but q = ΔH at constant pressure.

[Ariel Guan 1H]

you could look at the gibbs free energy equation where T must be constant and in K.

[Shruti Kulkarni 2I]

It's referencing Gibbs Free Energy! This shows that delta G = delta H - T delta S

[Ritika Prasad 1A]

The two equations you can use for this are:

1) ΔG= ΔH - TΔS or ΔS = -(ΔG - ΔH)/T or ΔH = ΔG + TΔS

2) ΔS= −ΔH/T or ΔH = -ΔST

[Lung Sheng Liang 3J]

Hello, an equation relating entropy with enthalpy is the Gibbs free energy equation. dG= dH - TdS

[Catie Donohue 2K]

To add on, the temperature will only need to be factored in to determine spontaneity when ∆S and ∆H are the same sign (one is negative and the other is positive). Using the equation, when ∆S and ∆H are both negative, the reaction will be spontaneous only at a lower threshold temperature. When ∆H and ∆S are both positive, the reaction will be spontaneous only at a higher threshold temperature.

[Abraham De Luna]

I think that it might be referring to the Gibbs free energy equation which is delta G= Delta H - T(DeltaS)

[Alisa Nagashima 1B]

This is referring to gibbs free energy: ΔG = ΔH - TΔS

[Moura Girgis 1F]

That would be Gibbs free energy equation in which (change in Gibbs free energy) is equal to (change in enthalpy) minus (temperature in Kelvins times change in entropy).

[Neha Jonnalagadda 2D]

The gibbs free energy equation works.

[Vincent Real 2C]

The relationship between entropy and enthalpy can be related by Gibb's Free Energy Equation. This equation is delta(G) = delta(H) - Temperature x delta(S), where entropy is represented by delta(S) and enthalpy is represented by delta(H). It is also worth noting that a rise in temperature (+H) is associated with a rise in disorder (+S), while a decrease in temperature is associated with an increase of order (-S).

[Reece Fong 2k]

Enthalpy and entropy are related through the equation ∆G = ∆H - T∆S

[Ashwin Vasudevan 3A]

This is referencing the Gibbs free energy.

[Yewon Jang 3K]

Hi! You would use the Gibbs Free Energy equation to find the relationship between entropy and enthalpy. The equation is deltaG=deltaH-T*deltaS

[SerenaSabedra]

Delta S relates to delta T in the concept of Gibbs free energy, given by the equation deltaG = deltaH - T*deltaS

[Brooke Gushiken 1B]

Hi! I was confused about this too, but I think they can be related through Gibbs Free Energy, which is determined by the equation ΔG = ΔH - TΔS. Hope this helps!

[Rena Wu 3E]

Hi Joshua, I believe this concept is referring to Gibbs Free Energy, where deltaG = deltaH - T*deltaS, where T = temp. In this equation, temperature and pressure are both constant. Hope this helps!