Calculate Temperature of Nitrogen Gas at 2 atm Pressure

[MisterP]

1. The problem statement, all variables and given/know
Given: Nitrogen: 2g, it takes 820cm³ at 2 atm pressure. What is the temperature (T) of gas? Answer: 280K

Homework Equations

P*V = n*R*T
P - pressure
V - velocity
n - moles?
R - constant, 0.0820 ? when I use liters, atm
T - temperature in kelvins

The Attempt at a Solution

At first I calculate moles. 2g/14 - 0,142 moles
Then use equation. 2atm * 0,82L = 0,142moles*0.082*T
And I get a totally different answer for T = 149K

 

[DrClaude]

Is it said that the gas is molecular nitrogen?

 

[MisterP]

It says: 2 grams of nitrogen

 

[DrClaude]

Isn't nitrogen usually found in molecular form, N₂?

 

[MisterP]

Should I use 2/28 ?

 

[DrClaude]

Yes, I would use 28 g/mol for the molecular mass of nitrogen.

 

[MisterP]

Yes, it works now :) I have not been learning physics since 2006. And now we had this 3 week physics course starting from mechanics up to electrics, that's why I am clumsy on these tasks :(

 

[DrClaude]

PF is there to help