I have 2.00 L of H2 at 475 torr, and 1.00L of N2 at 152 torr. If I combined the two into a 3.00L container, what would be my total pressure in torr? I'm looking for the process, not just the solution. Thanks for reading!

Question

I have 2.00 L of H2 at 475 torr, and 1.00L of N2 at 152 torr.  If I combined the two into a 3.00L container, what would be my total pressure in torr?  I'm looking for the process, not just the solution.  Thanks for reading!

anonymous · Answer

ok let me try to crack this one fast:
pV=nRT
so n doesnt change cause there is no loss to surroundings:
n= pV/RT
index 1 before and index 2 after mixing
n1=n2
p1V1/RT1=p2V2/RT2
you can cross out R and T cause they are constant
so you got
p1V1=p2V2
since you have 2 components:
p1V1+p2V2=p3V3
475 torr * 2 L + 1 L * 152 torr = p3 * 3 L
p3 = 367,33 torr

that is if i got it rigt cause im a bit tired its 1:33 AM

anonymous · Answer

Doing the math on my end, but the process looks right.  I'll get back with my solution.  Thanks for the reply!

anonymous · Answer

he he he i also remembered easier way to come to same result :D
1/3 * 152 + 2/3 * 475 = 367,33 torr 
:D

anonymous · Answer

367.33 torr is what I got.  Your second solution is much simpler!  I think I can remember that.  Thanks again Kryten!

anonymous · Answer

it comes from that famous law:
p(partial) = p * x 
and here x is volume parts cause we are talking about gasses :D

anonymous · Answer

Would that be Dalton's Law of Partial Pressures?

anonymous · Answer

yup :)