You are given the balanced chemical equation: c4h4 + 5o2 4co2 + 2h2o. if 0.3618 moles of c4h4 are allowed to react with 1.818 moles of o2, and this is the only reaction which occurs, what is the maximum mass of water that could be produced?

Since there are given data of two reagents, we need to obtain which of reagents are surplus.

0.3618 mol C4H4 - x mol O2
1 mol C4H4 - 5 mol O2


that means that there are too much O2 gas (by 0.009 mol)

so we continue counting using C4H4 data

0.3618 mol C4H4 - x mol H2O
1 mol C4H4 - 2 mol H2O


Mw(H2O)=2×1+16=18 g/mol

n=m/Mw

m=n×Mw


13.0248 grams of H2O