[semi_sonic18]

many water treatment plants use chlorine gas to kill microorganisms before the water is released for residential use. a plant engineer has to maintain the chlorine pressure in a tank below the 85.0-atm rating and, to be safe, decides to fill the tank to 80.0% of this maximum pressure. (a) how many moles of Cl2 gas can be kept in the 850.-L tank at 298K if she uses the ideal gas law in the calculation? (b) what is the tank pressure if she uses the van der Waals equation for this amount of gas? (c) Did the engineer fill the tank to the desired pressure?

[Padfoot]

Please show your attempt (if any).

Hint: Look at eqn, what information do you know?
http://www.ucl.ac.uk/Mathematics/geomath/rev/algandeq/eqn3.html