Which Gas Behaves Closest to an Ideal Gas?

[markosheehan]

out of the gasses hydrogen,nitrogen,chlorine, and helium which shows behviour closest to an ideal gas.?

ive been told the answer is helium because there is no attractive forces between helium atoms. would there not be van der waal forces though.? also would hydrogen just have as little attractive forces aswell?

also because hydrogen has only 1 electron so its smaller. so molecules are more widely spaced therefore its closer toeing a ideal gas. but I've been told helium is the right answer. using my logic it doesn't make sense

 

[I like Serena]

out of the gasses hydrogen,nitrogen,chlorine, and helium which shows behviour closest to an ideal gas.?

ive been told the answer is helium because there is no attractive forces between helium atoms. would there not be van der waal forces though.? also would hydrogen just have as little attractive forces aswell?

also because hydrogen has only 1 electron so its smaller. so molecules are more widely spaced therefore its closer toeing a ideal gas. but I've been told helium is the right answer. using my logic it doesn't make sense

Hi markosheehan,

Yes, there are Van der Waals forces in all cases.
However, Helium is the only one that is electrically neutral.
That's because it's the only one that is 'noble'. That is, the outer valence shell is fully loaded, giving the least electrical interactions.
So Helium is the one with isolated neutral $He$ atoms, while for instance hydrogen forms $H_2$ molecules due to its single valence electron. And those molecules have more electrical properties, since the charge is not divided uniformly. As a result $H_2$ molecules interact more with each other than $He$ atoms do.

Noble gasses (such as Helium) are known for their complete lack of interaction with anything.
That's why historically they were the last group of elements to be discovered at all.
It makes them the closest thing we have to ideal gasses.