Question
One mole of 
and one mole of CO are taken in a 10-litre vessel and heated to 725K. At equilibrium, 40% of water (by mass) reacts with carbon monoxide according to the equation
Calculate the equilibrium constant for the reaction.
Solution
40% by mass of water = 40% by mole of water
40% of one mole of water = 
Initial mole 1 1 0 0
Final mole 1-0.4 1-0.4 0.4 0.4
= 0.6 = 0.6
According to the law of chemical equilibrium,
Substituting the values, we have,
