[bamster]

we did a lab where we added 7.5 grams of maleic anhydride to boiling water to get crystals of maleic acid. We filtered it and got 2. something grams of it. It says to calculate the percent yield, but it doesn't give the amount you should get at the end.
Is this the right equation for the reaction

C₂H₂(CO)₂O  + H₂O  C₄H₄O₄

I believe its already balanced. I just don't understand how you know what mass you should get from the equation?