CO2 temperatur and pressure effects

[yuku]

Hello All,

I am a bit stuck with the following problem:

Consider a chilled can of sparkling/carbonated water. At 3◦C, the pressure inside the can is equivalent to 2.0 atmospheres. What is the total concentration of dissolved inorganic carbon in the water, assuming only a carbon dioxide + water system? Now, model an increase in temperature to 25◦C. What is the resultant pressure? What is the pH of the water?

My approach doesn't really worked:

TITLE Simple Pressure and Temperatur effects

SOLUTION 1
   temp   3
   pH   7
   pressure 2
   units mmol/kgw
   density    1
   -water   1 # kg

EQUILIBRIUM_PHASES 1
   CO2(g)   -2.5   10

GAS_PHASE 1
   -fixed_volume
   -equilibrate with solution 1
   -volume 1
   CO2(g)   2

REACTION_TEMPERATURE 1
   25

END

Thanks for any help.

[dlparkhurst]

I assumed the head space in the bottle is 0.01 L with 1 L water. The pressure increases to 4 atm and the pH actually decreases from 3.7 to 3.6.

Code: [Select]

SOLUTION 1
   temp   3
   pH   7 charge
   pressure 2
   C(4)     1 CO2(g) 0.3 # log10(2)
END
GAS_PHASE 1
   -fixed_volume
   -volume 0.01
   -temp 3
   CO2(g)   2
END
USE solution 1
USE gas_phase 1
REACTION_TEMPERATURE 1
  25
END