a)
initial concentration of SO3 = number of moles/ volume
                                                       Â
= 2 mol / 2L
                                                       Â
= 1 mol/L
2 SO3 (g) → 2 SO2 (g) + O2 (g)
1Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
0Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
0Â Â Â (initial concentration)
1-2x                   Â
2x             Â
x   (at equilibrium)
But given that equilibrium concentration of SO3 = 0.4
mol/L
so,
1-2x = 0.4
x= 0.3 mol/L
equilibrium concentration of SO2 = 2x = 2*0.3 = 0.6
mol/L
equilibrium concentration of O2 = x = 0.3 mol/L
b)
Kc = [SO2]^2 [O2] / [SO3]^2
     = 0.6^2 *0.3/ {0.4^2}
     = 0.675
use:
Kp = Kc* (RT)^ (delta n)
     = 0.675* (0.0821*700)^ (2+1-2)
     = 0.675* (0.0821*700)^1
     = 0.675* (0.0821*700)
      =38.8
