# Thermodynamics question

1. Mar 31, 2014

### Hozhoz

1. The problem statement, all variables and given/known data
two bulbs of volumes 200cm^3 and 100cm^3 are connected by a short tube containing an insulating porous plug that permits equalization of pressure but not of temperature between bulbs. the system is sealed at 27°c when it contains oxygen under a pressure of 1 bar. the small bulb is immersed in an ice bath at 0°c and the large bulb is placed in a steam bath at 100°c. what is the final pressure inside the system ? neglect thermal expansion of the bulbs.
thank you.

2. Relevant equations

3. The attempt at a solution
i assume that the condition here is isobaric

2. Mar 31, 2014

### Staff: Mentor

It's not isobaric. The pressure changes in both containers to the same new value.

From the ideal gas law, how many moles of gas are present in each bulb to start with? Let Δn be the change in the number of moles in the small container. What is the change in the number of moles in the larger container, and, in terms of Δn, what are the final number of moles of gas in each of the two containers?

Chet

3. Mar 31, 2014

### Hozhoz

it didnt give me the value of n

4. Mar 31, 2014

### Staff: Mentor

It gave you $P$, $V$, and $T$. Can't you figure out $n$?

5. Mar 31, 2014

### Hozhoz

oh yeah pv=nRT