(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

You have a balloon (stretchy) filled with one liter of He at 1 atm and 298 Kalvin. The balloon is suddenly placed into a room at .5 atm and 298 Kalvin. What is the temperature of the gas inside the balloon a little while after this happens?

2. Relevant equations

P*V=n*R*T

3. The attempt at a solution

So first, I calculated the number of moles of He in the balloon, using the ideal gas law as follows...

(1 atm)*(1 L)=n*.0821*(298 K)

n=.0409 mol

Then, I said that...

P1*V1=P2*V2

(1atm)*(1L)=(.5atm)*(V2)

therefore, V2 = 2L

From there, (using ideal gas law again...)

(.5atm)*(2L)=.0409 mol(.0821)*(T)

T=298K

but this answer didn't make sense to me...shouldn't temperature in the balloon change?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Ideal Gas Law Problem

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