Calculating the total and partial pressure of gas mixture

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SUMMARY

The discussion centers on calculating the total and partial pressures of a gas mixture consisting of 1 mole of O2 and N2 gas at 5 atm in a 1 L flask at 10 degrees Celsius. Using the ideal gas law, the total moles of gas were calculated to be 1.2153, leading to a total pressure of 28.22 atm and a partial pressure of O2 at 23.22 atm. The problem arises when considering the escape of 2 moles of gas, which exceeds the total moles present, resulting in an impossible scenario. The conclusion drawn is that if 2 moles escape, the system would effectively have zero pressure.

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Lester_01
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1. The problem/question is as follows:

1 mole of O2 mixed with N2 gas (PN2= 5 atm at 10 degrees celsius in a 1 L flask. What is the total pressure after 2 moles of gas is allowed to escape? How about the partial pressure of O2?

R= 0.08206\frac{L atm}{mol K}

Homework Equations


Using the ideal gas law, I have calculated the quantity of moles of nitrogen gas in the mixture, I add one mol of oxygen and it results in 1.2153 moles total. The problem states that 2 moles of gas are allowed to escape, yet there is not even 2 moles of gas in the system. We can't have negative moles so the situation seems impossible, or a poorly designed question at best.

The Attempt at a Solution



Ptot= ∑PO2 + PN2

nN2=\frac{PV}{RT}

= \frac{(5)(1)}{(0.08206)(283)}

= 0.2153 moles N2

ntot = 1 + 0.2153 = 1.2153 moles total

PN2= Ptot /frac{n<sub>N<sub>2</sub></sub>}{n<sub>tot</sub>}

5= P<sub>tot</sub>\frac{0.2153}{1.2153}

\frac{5}{0.1772}= Ptot= 28.22 atm

PO2= 23.22 atmThese values seem to make sense, but I'm not sure how to reconcile for how 2 moles are escaping.

Interestingly, if I subtract 2 moles from the 1.2153 and in corporate that into the procedure as ntot, it will result in a negative total pressure of -18 atm, and also interestingly result in PO2= -23.22 atm (the opposite of the result above)


Any information regarding how 2 moles can escape out when there is only 1.2153 moles contained?

PS Sorry about the coding, it for some reason isn't working very well.
 
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Or I'm thinking the answer could simply be zero for both cases because all particles of gas have escaped, all the moles are gone and there's no pressure in the flask in that case.
 

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