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One of my teacher said that the one with more molecular mass will deviate more from behaving as an ideal gas and he showed a graph given below.
Is his statement is correct? If no, then what's the reason?
In th graph $\ce{CO2}$ have higher molecular mass than other gases and its deviation is more than others, so from his point of view his statement is OK?
If there are any other reason please give me with easy language to understand.
N. B. If the question is not clear, please comment.
One of my teacher said that the one with more Molecular mass will deviate more from behaveing as ideal gas and he showed a graph given below
Yes, that's basically correct. But it has to be understood as a general trend, to which many exceptions can be found (especially when the Molecular Masses are close).
Ideal gases would be made up of point masses (taking up no volume at all) that collide perfectly elastically.
Real gases are made up of real masses that take up some volume (just condense them to see that) and substances with higher Molecular Mass (MM) tend to have larger molecules that take up more volume.
Secondly, higher MM usually means larger electron clouds surrounding the nucei. During collisions, due to transient polarisation (the electron clouds repell each other, remember?), there's more interaction (Van der Waals forces) between larger molecules. Larger molecules tend to be more polarisable.
So by and large, smaller molecules/atoms behave more ideally.
