Carbon monoxide and molecular oxygen react to form carbon dioxide. A 49.0 L reactor at 200°C is charged with 1.14 atm of CO. The gas is then pressurized with O2 to give a total pressure of 3.54 atm. The reactor is sealed, heated to 350°C to drive the reaction to completion, and cooled back to 200°C. Compute the final partial pressure of each gas.
P CO
P O2
P CO2
Not sure how to go about this
You will need a balanced equation.
Use PV = nRT and 1.14 atm to calculate n for mols CO to start. Then use PV = nRT and total P to solve for total mols. Total mols minus CO mols = mols O2 added. I suspect this is a limiting reagent problem but regardless you check that as a possibility. If yes or no you will need the limiting reagent. Calculate mols CO2 formed and mols CO or O2 left (I suspect one will be zero). The use PV - nRT and solve for p of each gas. Post your work if you get stuck.
So I figured CO to be the limiting reagent spans then I found the amount of predicted moles of CO2 to be the same which makes sense right? So after this do I just plug the moles back in for their respective n values?
Not yet. You're right that mols CO2 = mols CO since that is the limiting reagent and 2 mol CO2 are formed for 2 mols CO initially. Next you calculate mols O2 used by that 1.44 mols CO, subtract from th 3.03 mols O2 you started with (3.03 is what I calculated but you need to confirm that. It's late and I'm having trouble seeing.) THEN you have mols CO(zero), mols O2 left unreacted, and mols CO2 formed. Plug those moles back in individually at the new conditions listed and solve for the pressure of each. I may not be able to check your final work because I'm headed to bed but you seem to have this well under control.
To solve this problem, we can use the Ideal Gas Law and the concept of partial pressure. The Ideal Gas Law equation is expressed as: PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.
To find the final partial pressure of each gas, we can follow these steps:
Step 1: Convert temperatures from Celsius to Kelvin
200°C + 273.15 = 473.15 K
350°C + 273.15 = 623.15 K
Step 2: Calculate the number of moles of CO using the given conditions
We can use the Ideal Gas Law equation to calculate this. Rearranging the equation as n = PV / RT, we can plug in the values:
nCO = (1.14 atm * 49.0 L) / (0.08206 L atm/mol K * 473.15 K)
Step 3: Calculate the number of moles of O2 using the given conditions
Since the total pressure is given, we can subtract the initial partial pressure of CO from it to get the partial pressure of O2:
PO2 = 3.54 atm - 1.14 atm
Step 4: Calculate the number of moles of CO2 formed at the end
Since the reaction goes to completion, all the CO will react, producing the same moles of CO2:
nCO2 = nCO
Step 5: Calculate the final partial pressures of each gas
Using the Ideal Gas Law equation, we can calculate the final partial pressures:
PCO = nCO * RT / V
PO2 = nO2 * RT / V
PCO2 = nCO2 * RT / V
Now, we can plug in the values and solve for each partial pressure using the values from the previous steps.
Please note that the unit for R in the Ideal Gas Law equation is L atm / mol K.