One mole H ₂ O ( g ) and one mole CO ( g ) are taken in 1 ~L flask and heated to 725 ~K . At equilibrium, 40 % (by mass) of water reacted with CO ( g ) as follows H ₂ O ( g )+ CO ( g ) H ₂( ~g )+ CO ₂( ~g ) Its K _ c value is

Step-by-step solution

Number of moles of H ₂ O reacting =40 % of 1 mole =0.4 moles ( degree of dissociation = ) 0.4 moles of CO and 0.4 moles of H ₂ O react. Let C = initial concentrations of H ₂ O and CO . At equilibrium; aligned & [ H ₂ O ]= 0.6 ~mol 1 ~L =0.6 M & [ CO ]= 0.6 ~mol 1 ~L =0.6 M & [ H ₂ ]= [ CO ₂ ]= c =1 0.4=0.4 M & K _ c = [ H ₂ ] [ CO ₂ ] [ H ₂ O ] = (0.4)(0.4) (0.6)(0.6) & =0.444 . aligned