Finding the total translational KE of 1kg of Neon

[Will Griffiths]

Homework Statement

The screen shot I have attached is the original question, I think I'm ok up until the Ne part.
My answer just seems like a ridiculous number, I haven't had much experience with this so don't really know what an 'normal' KE for 1kg of gas would be.

Homework Equations

The Attempt at a Solution

Hopefully it's clear what I've done. The solution to the first part (deriving and expression for the mean translational KE...) is the equation I start with, if that is wrong then please let me know.
EDIT - have just realized I put the final answer as 5.49... it should be 2.49.

 

[PietKuip]

My answer just seems like a ridiculous number, I haven't had much experience with this so don't really know what an 'normal' KE for 1kg of gas would be.

The translational kinetic energy per mole is 3/2 RT for any ideal gas.
Neon is quite light, so there are many moles in a kilogram.

 

[Will Griffiths]

The translational kinetic energy per mole is 3/2 RT for any ideal gas.
Neon is quite light, so there are many moles in a kilogram.

Yes there are 50 moles. Do you think my answer is correct then? :)

 

[PietKuip]

Avoid calculating with numbers that are so large or small that you do not have any intuition for it.
The basic number to remember is the gas constant, 8.3 joule per mole per kelvin. That way you can be more confident about your answer.

 

[Will Griffiths]

Avoid calculating with numbers that are so large or small that you do not have any intuition for it.
The basic number to remember is the gas constant, 8.3 joule per mole per kelvin. That way you can be more confident about your answer.

Ok, thanks for your advice :)