# Dependence of Van der Waal's constants with distance

Shouldn't the constant change as the intermolecular forces vary at different distances?

Or is it the case that the constants have nothing to do with the forces because we are using the 4 gas laws i.e Charles,Boyles, Avogadros and Gay-lussac laws?

• The said laws have nothing to do with forces and constants, because they are strictly valid for ideal gases only. Constants do have something to do with forces, but not in the way you seem to think. – Ivan Neretin Nov 22 '17 at 15:55

the constants are a value which show the trend of a proportionality. Eg.

P(total) is given by --> P(real) + (an^2)/V^2

here a is a van der waals constant. it actually specifies the trend or the rate of increase of decrease in the expression (an^2/V^2) and not some force. n^2/V^2 provides us the necessary pressure change.

thus the constants 'a' and 'b' remain constant, of course, for a particular gas.

this is what my understanding is. Hope this helps