The real purpose of this problem is for you to realize that the gases and their pressures are independent of each other; i.e., You have Liters, partial pressure of CO2, and T. So use PV = nRT, solve for n to find moles, then mols = grams/molar mass to find grams. Remember to convert T to kelvin.
Post your work if you get stuck.
The partial pressures of the four gases contained in a 6 L cylinder at 100 °C were: CO2 = 63.1 atm; H2 = 21.1atm; CO = 84.2 atm; H2O = 31.6 atm. How many grams of CO2 were in the cylinder?
Can someone please help me. These pressure/gas problems are so difficult for me as I can never seem to do much of them
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So that means I don't need the partial pressure of H2, CO and H2O?
That's right. Dalton's law tells us that each gas has a partial pressure that is its own and is independent of other gases present in the mixture. So you know the pressure of the CO2 will give you the mols from PV = nRT FOR CO2. You could find mols and grams for each of the other gases, too. The total pressure of course is the sum of each of the partial pressures.
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