The internal energy of a monoatomic ideal gas such as neon is simply the total kinetic energy of all its atoms.
What is the internal energy of 2 liters of neon at a temperature of 200 K and pressure of 0.7 atm?
PV = nRT
KE(ave) = 3/2kT
U = 3/2nRT
The Attempt at a Solution
KE = 1/2mv^2
From a previous problem, I figured out that v(rms) = 499.227 m/s.
And, 2 liters of neon X 0.9002 g/L (density of neon) = 0.0018004 kg
KE = 1/2(0.0018004 kg)(499.227 m/s) = 224.3546833 J (wrong answer)
I feel like I am approaching this problem in the wrong manner. Please help!