Calculating pressure

[geranimo]

I'm trying to figure out the pressure calculations.

Say I want 2.5 volumes of co2, which is ~60L of co2 at 293K at 100kPa. Using PV = nRT I get 2.64mol of co2 dissolved in a keg. Next I use Henry's law with Kh = 0.035 and I get 55 PSI of pressure at equilibrium, which I find not very likely. Anyone knows where my calculations fails?

 

[hvjackson]

Your calculation is failing because the ideal gas law is not applicable to this situation where you have a mixture of liquid and gas. The solubility of CO2 in water is not determined by the ideal gas law.

 

[geranimo]

No. I use the ideal gas law to get the number of moles of co2 dissolved with the definition of what is a volume of co2.

 

[RPh_Guy]

At 20C should be 27.6 psi (using online calculator). Can't help with the math, sorry.