What is the correct way to find the temperature of helium in this scenario?

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To find the temperature of helium in a pressure vessel, the correct formula involves the ideal gas law, PV = nRT, where n cannot be directly replaced by density. The initial calculation yielded an unreasonably high temperature of 70000 K, indicating a mistake in the approach. The discussion emphasizes expressing the number of moles in terms of known values for helium. After clarification, the user acknowledged the error in their formula and indicated they found the correct answer. Understanding the relationship between pressure, volume, and temperature is crucial in solving gas-related problems.
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Homework Statement


Helium is kept in a pressure vessel at a pressure of 5.42 bar and the resulting density is 0.92 kg/m3. The gas constant R is 8.314 J/(mol*K). The volume of the vessel is 1589.194 m3. I need to find the temperature of helium in Celsius.

Homework Equations


pressure(Pa)=density(kg/m3)*R*temperature(K)

The Attempt at a Solution


With the formula given, I got the answer of 70000 K which is logically not correct.
 
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Hi Angelina21,

Welcome to Physics Forums!

PV = nRT

You can't simply replace n (number of moles) with density. Try expressing n in terms of things you know about helium in general and the helium in this case.
 
gneill said:
Hi Angelina21,

Welcome to Physics Forums!

PV = nRT

You can't simply replace n (number of moles) with density. Try expressing n in terms of things you know about helium in general and the helium in this case.
I think I got the answer now. My formula was indeed wrong. Thanks!
 
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