One mole of `H_(2)O` and one mole of `CO` are taken in a `10 litre` vessel and heated to `725 K`. At equilibrium, `40 per cent` of water (by mass) reacts with carbon monoxide according to the equation,
`H_(2)O_((g))+CO_((g))hArrH_(2(g))+CO_(2(g))`
Calculate the equilibrium constant for the reaction.