How to determine Chemical potential

[marie2010]

hi,
what is the chemical potential of N2, CO, or NH3 molecules in a gas phase? How to determine it?
Thanks.

 

[Hyla Brook]

The chemical potential is defined usually by the partial derivative of Gibbs energy with respect to the qantity of the component, under the condition that the temperature, pressure and the quantities of other components are constant.

 

[marie2010]

hi,
thanks for your answer. What do you mean by the component (especially in case of CO)? Also, so what would be the chemical potential of N2 at ambient conditions?
I appreciate your help.

 

[DrDu]

Maybe looking up "Sackur Tetrode equation" might be helpful.

 

[Hyla Brook]

The definition I provided is the general definition in multi-component system. It of course serves the single component system. That is the increment of Gibbs energy brought about by increasing unit quantity of, e.g. CO. This definition of chemical potential can be found in any textbooks of thermodynamics. The ambient condition here corresponds to the constant temperature and pressure. For more, you can work it out on your own I think. Hope it help.

 

[guyingfei]

I regard chemical potential as a parameter to control the particle numbers. I hope the idea could help you. I remeber chemical potential was first introduced as lagrange mutiplyier in statistics mechanics.

 

[marie2010]

Thanks for your explanation. They all help a lot!