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