For a real gas (mol. mass = 60 ),if density at critical point is 0.80 gcm3 and its Tc=4×105821K.Find the Van der Waals constant “a”(in atm L2 mol−2 ) .
3.375
Vc=600.80=75 cm3 mol−1
b = Vc3=25 cm3 mol−1 = 0.025 mol−1
Tc=8a27Rb
4×105821=8×a27×0.0821×0.025
⇒a = 3.375