Question

Question 17

The equilibrium constant for the reaction

SO_2(gas)+NO_2(gas)<=====>SO_3(gas)+NO_{(gas) is 3.1}

Find the amount if NO₂ that must be added to 2.3mol of SO₂ in order to form 1.2mol of SO₃ at equilibrium.

Answer 1

        SO2(gas) + NO2(gas)<=====>SO3(gas)   + NO(gas)

initial 2.3 mol       x              0                0

change    1.2 mol      1.2 mol       1.2 mol          1.2 mol

equil    1.1 mol      x-1.2 mol      1.2 mol          1.2 mol

     Kc = [NO][SO3]/[NO2][SO2]

     3.1 = (1.2*1.2)/(1.1*(x-1.2))

x = no of mol of NO2 must be added = 1.622 mol