v ÒaÓ and
ÒbÓ are determined
by experiment
v ÒaÓ and
ÒbÓ are different for each
gas
v bigger
molecules have larger ÒbÓ
v ÒaÓ
depends on both size and polarity
Johannes
Diderik van der Waals
Mathematician
& Physicist
Leyden, The
Netherlands
November 23, 1837
– March 8, 1923