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What is the partial pressure of CO2? What is the total pressure in the container?
Dry ice weighs 2g in a sealed 1L container filled with air (25 degrees celsius) @ STP. The ice sublimes and the temperature returns to 25 degrees.
22.045 X 8.31 X 298
Is this correct?
P total = P(air) + P (Co2)
+ 101.3 Kpa + 111.4 Kpa
=212.7 Kpa or 2.1 atm correct?
- Dr WLv 71 decade agoFavorite Answer
total pressure = partial pressure CO2 + partial pressure air
partial pressure air = 1 atm...(STP)
**** actually, STP is OC and 1 atm.. not 25C and 1 atm... 25 C and 1 atm is what the US EPA uses for standard conditions.. see the source...regardless. 25C and 1 atm it is...*****
so let's find PCO2...
PV = nRT
P = nRT/V
n = 2 g CO2 x (1 mole CO2 / 44.0 g) = 0.004535 moles
R = 0.0821 Latm/moleK
T = 25C = 298.15K...
V = 1 L
PCO2 = (0.004535 moles) x (0.0821 Latm/moleK) x (298K) / (1 L) = 0.1 atm... 1 sig fig since 2g has 1 sig fig..
total pressure = pressure air + pressure CO2 = 1.1 atm.
your calculation of moles was incorrect.
my other suggestion is that you follow through on the units..
- pisgahchemistLv 71 decade ago
No, 54592 atm is absurdly high.
You don't have 22.045 moles, you have 0.04545 mol of CO2
R can be 8.314 LkPa/molK if you want pressure in kPa, or you can use 0.0821 Latm/molK to get the pressure in atm.
PV = nRT
PV = mRT / M where m = mass, M = molar mass
P = mRT / VM
P = 2.00g x 0.0821 Latm/molK x 298K / 1.00L / 44.0g/mol = 1.11 atm