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View Full Version : Volume of Gas At Standard Condition ? Which Gas Law ?


benworld
Apr7-10, 05:08 PM
1. The problem statement, all variables and given/known data

A Sample of gas 250 mL at 37 C and 730 torr . What volume would gas occupy at standard conditions ?

2. Relevant equations

pv = nRT

V2 = T2P1V1
-------
T1P2


3. The attempt at a solution

Sample Gas

V = 250 mL ( 0.250 L )
P = 730 torr ( .960 atm )
T = 310 K

Standard Condition

T = 273
V = 22.4 L
P = 1 atm

I'm confused because sample gas formula is already given and then find the gas under stand condition ?

Do I just use standard condition formula and drop the other ones ?


If I use pv = nRT then I get following

v = (0.250 L / 22.4 L = .0111 mol) since STP 1 mol = 22.4 L
p = .960 atm
R = 0.08260 ( constant gas )
T = 310 K

v = (.0111 mol ) (0.08260)(310)
--------------------------
.960 atm

Answer = .290 L

The answer doesn't seem to make sense. Any correction ?

flyers
Apr7-10, 05:18 PM
I think you are only supposed to use the temperature and pressure at STP and use the equation

PV/T = PV/T

Borek
Apr7-10, 05:32 PM
Good that you see that answer doesn't make sense. You are lowering temperature and increasing pressure, volume can't go up.

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benworld
Apr7-10, 05:45 PM
I got the answer..211 mL.. user p1v1/t2 = p2v2/t2

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