The Van der Waals' Equation is as follows:
where a is the polarity coefficient, which accounts for the attractive or repulsive interactions of the gas molecules, and b is the size coefficient, which accounts for the size of the individual gas molecules. This equation show how real gases deviate from ideal behavior.
Let P + n2a/V2 = Pvdw, the van der Waals pressure. We can rearrange this equation to get Pvdw:
The reaction of H2 and O2 to form H2O is as follows:
2 H2(g) + O2(g) → 2 H2O(g)
We're given T = 23.8˚C + 273.15 = 296.95 K.
To study a key fuel-cell reaction, a chemical engineer has 20.0-L tanks of H 2 and of O2 and wants to use up both tanks to form 28.0 mol of water at 23.8°C.
(b) Use the van der Waals equation to find the pressure needed in each tank.