1. The problem statement, all variables and given/known data Hello! I would be grateful for your help on finding my mistake - somehow my answers are wrong compared to the answer from the book. Here is the exercise from a paragraph on gases (cumulative gas law, basics): Consider the reaction for the synthesis of nitric acid: 3NO2 + H2O = 2HNO3 + NO (a) If 12.8 L of NO2 measured at STP, is allowed to react with 14.9 g of water, find the limiting reagent and the theoretical yield of HNO3 in grams. Here is my solution: 1 mole of gas at STP = 22.4 L; 12.8 L gives 0.5714 moles of NO2 1 mole of H2O = 18.016 g; 14.9 g = 0.827 moles of H2O The limiting reagent is NO2, because 3 moles NO2 + 2 moles of H2O 0.5714 moles NO2 requires only 0.381 moles of H2O, but we have 0.827 moles of H2O 1 mole of NO2 = 46.007 g 0.5714 moles of NO2 = 26.288 g Theoretical yield of HNO3: 3 moles of NO2 = 2 moles of HNO3 0.5714 moles of NO2 = 0.3809 moles of HNO3 1 mole of HNO3 = 63.008 0.3809 moles of HNO3 = 24.001 g Thank you!