How Can I Measure Free Energy and Enthalpy of Reactions?

In summary, the conversation discussed a project on determining ways to measure free energy and enthalpy of reactions. The researcher was looking for information on equipment and procedures and was provided with resources such as textbooks and physical chemistry experiments. The conversation also mentioned the use of standard enthalpies of formation and devices like a calorimeter or bomb calorimeter to calculate enthalpy and Gibbs free energy.
  • #1
gee
6
0
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.
 
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  • #2
For the second time, you are going to have to be more specific. What types of reactions? What conditions? What resource constraints?
 
  • #3
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
J. R. Partington, Advanced Treatise on Physical Chemistry; Weissberger, Physical Methods of Organic Chemistry; Shoemaker and Garland, Experiments in Physical Chemistry.
 
  • #5
To find the enthalpy and gibbs free energys you can use standadard entyhapys of formation (found in any textbook)

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
 

1. How is free energy defined?

Free energy, also known as Gibbs free energy, is a thermodynamic quantity that represents the amount of energy available for a system to do work at a constant temperature and pressure.

2. What is the equation for calculating free energy?

The equation for calculating free energy is ΔG = ΔH - TΔS, where ΔG is the change in free energy, ΔH is the change in enthalpy, T is the temperature in Kelvin, and ΔS is the change in entropy.

3. How is free energy measured in a laboratory setting?

Free energy is typically measured using a calorimeter, which is a device that measures the heat released or absorbed by a chemical reaction at a constant pressure. The change in temperature of the reaction is used to calculate the change in enthalpy, which is then used to calculate the free energy.

4. Can free energy be negative?

Yes, free energy can be negative. A negative value indicates that the reaction is spontaneous and releases energy. This means that the reactants have a higher free energy than the products, and the reaction will occur without an external energy source.

5. What factors affect the measurement of free energy?

The measurement of free energy can be affected by temperature, pressure, and the concentrations of the reactants and products. Changes in any of these factors can alter the free energy of a reaction and affect its spontaneity.

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