Undergrad Understanding Boiling Point Elevation: Real Gas Law and Its Impact on Molecules

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The discussion centers on the ideal gas law and its modification into the real gas law, highlighting how molecular volume and interactions affect boiling point elevation. It is noted that boiling point increases as larger molecules hinder the transition of liquid atoms to vapor, thereby reducing vapor pressure. The conversation acknowledges that colligative properties depend on the number of solute particles, with boiling point elevation typically measured under ideal conditions of infinite dilution. However, for macromolecules, these interactions become significant, as explained by the Flory-Huggins theory. Understanding these principles is crucial for comprehending how molecular size influences boiling point elevation in real-world scenarios.
Biker
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So was thinking a little bit about the ideal gas law.
##P V = n R T##
And I read an article about the real gas law where they just edited few properties.
##(P + \frac{n^2 a}{v^2}) (V - nb) = n R T ##
Where a and b are constant determined experimentally.

So going back to our original point, Why doesn't the boiling point elevation have something related to the volume of the molecules or atoms?

And we know that the boiling point increases because of how the molecules prevent some of the liquid atoms to change into vapor state which reduces the vapor pressure in result increasing the boiling point.

So if we believe that this is what actually happen then bigger molecules/atoms will prevent more of the liquid atoms to change into vapor state which increases the boiling point.

What is happening here?

P.s I know that colligative properties only depend on how many solute particles.
 
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DrDu said:
These effects exist but the boiling point increase is usually reported for infinite dilution where solutions behave ideally.
But for macromolecules, these effects become very important, cf. the Flory Huggins theory:
https://en.wikipedia.org/wiki/Flory–Huggins_solution_theory
Oh that is actually great. Didn't know that there is a theory already there. Thank you!
 
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