# Van der Walls constant a

The sources are:

• Values are taken from the engineering toolbox .
• The Van der Waals equation uses liter (L) as unit for the volume (V).
• To convert a into atm L$^2$/mol$^2$ multiply by 0.986 atm/bar
• To convert a into kPa.L$^2$/mol$^2$ multiply by 100 kPa/bar

Symbol
$a_{VdW}$
Unit
bar.L$^2$/mol$^2$
Used in
$p_{VdW}$
Choices
GasFormulaValue
Air-1.358
N2N21.37
SF6SF67.857
CO2CO23.658
COCO1.472
O2O21.382
H2H20.2453
NH3NH34.225
SO2SO26.865
HeHe0.0346
ArAr1.355
KrKr2.325
XeXe4.192