# Free energy how to measure it

1. Mar 9, 2004

### gee

Hi everybody,
I'm working on a project aiming to determine what are the differents ways to measure the free energy (gibbs) and the enthalpy of reactions.
And I have no idea.
If you know some equipments or some procedure to measure it or also where i should look for it, I would be very happy.

Thank you very much in advance.

2. Mar 9, 2004

### Bystander

For the second time, you are going to have to be more specific. What types of reactions? What conditions? What resource constraints?

3. Mar 10, 2004

### gee

free energy

Hi, thank you for the attention that you pay to my question.
Acutally, My ressearch is broad. I've tried to find information but i found nothing. I just want to know the names of equipments and procedures that are the most used to measure free energy (and enthalpy). In a second time, when i will know a little bit more about it, i will orient my ressearch in a more specific way.
But for now, I need clues.

Thank you in advance.

4. Mar 10, 2004

### Bystander

J. R. Partington, Advanced Treatise on Physical Chemistry; Weissberger, Physical Methods of Organic Chemistry; Shoemaker and Garland, Experiments in Physical Chemistry.

5. Mar 11, 2004

### bjon-07

To find the enthalpy and gibbs free energys you can use standadard entyhapys of formation (found in any text book)

Experimentaly you can use an caliometer or a bombcalimoter. These devices will mechaure the heat change of the surroundings (therm system). With these values you can determine the enthaply by the following eq. (@ constant pressure) /delta H = /Delta T times nC; where H equals enthalpy and /delta T equals change in tempature of system and C equals molar heat capaicity and n equals quantily of substnace. For there to calculating the gibbs free energy is easy
/delta G = /delta H - T(/delta S) ; where delta S equals entropy = q (reverse)/Tempature