How many moles of CO will be produced, if 32.5grams of H2O are produced?

C6H6S+6O2=>6CO+3H2O+SO3

The given equation is already balanced. So the ratio of mol number of the production is the same as the ratio of the number before the production. 32.5 grams of H2O equals to 32.5/18=1.8 mol. The mole number of CO is 1.8/3*6=3.6 mol.