Ideal Gas Law and pressure in a holder

AI Thread Summary
The discussion revolves around calculating the pressure of argon gas in a 50.0 L container at 20°C using the Ideal Gas Law. Initial calculations yielded an implausibly high pressure of 25258 atm due to an incorrect molar mass of argon. Upon correction, the proper molar mass of argon is identified as 39.95 g/mol, leading to a revised pressure calculation of approximately 1265.1 atm. The confusion stemmed from mistakenly considering argon as diatomic gas. The final correct pressure, after adjustments, is 1.27 x 10^3 atm.
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Homework Statement


What is the pressure inside a $50.0$ L container holding $105.0$ kg of argon gas at $20^\circ$ C?

Homework Equations


Ideal Gas Law: PV=nRT

The Attempt at a Solution


From the ideal gas law, I get
<br /> P=\frac{nRT}{V}=\frac{\frac{105.0\times 10^3g}{36g/mol}\times 0.08214\frac{L\cdot atm}{mol\cdot K}\times 293^\circ K}{50.0 L}=25258atm<br />
which seems much too large. Am I doing something wrong?
 
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Nope! Your answer is quite reasonable, and it seems like nothing looks wrong in your setup of P= nRT/V and all the units match, your value for R is correct and you've converted C to K. Unless you made a calculating mistake, everything looks correct to me.
 
Oh wow, thanks! It's hard to believe the massive pressure inside, which was why I was skeptical. Thanks again.
 
On second glance, your molar mass for Argon seems to be off, also, you've made a calculation error. Try again and tell me what you got. (I've worked it out this time).
 
Oh, should it be 39.95\times 2 since it's diatomic?
 
Nono, on the work you've showed in your original post, it looks like you've put 36 g/mol.
 
But the molecular mass of Argon is 39.95 isn't it? I'm just substituting the 36 for 39.95x2.
 
By looking at the problem you've presented it should look like this:

P = [(105000/39.95)(0.08214)(293)]/(50)
P = 1265.1 atm
P = 1.27 x 10^3 atm

I've left out the units for simplicity, but you should write them in yourself.
 
Oh, yeah. For some reason I thought argon was diatomic...
 
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