Ideal Gas Question Please do help I'm befuddled

[arsey1009]

There are 2 identical vessels X and Y and they are connected like this by a tube of negligible volume:

X==========Y


they have a pressure of p and same temperature of T


Y is then heated, increasing it's temperature from T to 2T.

what is the final total pressure in terms of p?






I used Dalton's Law, so I assumed that the pressure in each vessel was actually 0.5p. I then used the equation

PfVf = PxVx + PyVy

but I could never get the answer which is 1.33p! ):





Could someone please help? Thank you very much! (:

 

[SteamKing]

I don't think Dalton's law is the best approach. Dalton's law deals with mixtures of different gasses and the partial pressures of each component. I think a better approach would be to use the combined gas law, PV/T = constant. This law relates pressure, volume, and temperature, which Dalton's Law does not.

 

[ideasrule]

Also, why is the pressure in each vessel 0.5p? The question says that it's p.