# Two separate flasks are each filled with a gas at 25 degrees Celsius; the valve betwe

1. Dec 10, 2009

### stacker

Two separate flasks are each filled with a gas at 25 degrees Celsius; the valve between them is opened and the gases are allowed to mix. What would be the final pressure in torr after mixing, if initially F2 is in the first flask (Volume = 2 L) at 271.78 torr and N2 is in the second flask (Volume = 1 L) at 372.79 torr?
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Here's my approach. I will determine the moles of F2 and N2 using the PV = nRT equation. This equation will give me the two mole values. Then I will use the fact that Xa = (na/ntotal) = Pa/Ptotal

Doing this, I got the answer to be 0.6028618419 in atm and 458.1749998 torrs.

Could someone confirm or correct me please.

Last edited: Dec 10, 2009
2. Dec 13, 2009

### omkar13

Re: Two separate flasks are each filled with a gas at 25 degrees Celsius; the valve b

sorry i didnt understood you my way of approach will be total no of moles are constant at const. temp
Hence P=(P1V1+P2V2)/(V1+V2) where P is final pressure after mixing