1. The problem statement, all variables and given/known data Many fertilizers contain ammonium phosphate as a source of phosphorus and nitrogen. A 7.225 g sample of a fertilizer is dissolved in water and mixed with excess barium chloride solution, and the following reaction occurs: 2(NH4)3PO4(aq) + 3BaCl2(aq) -> Ba3(PO4)2(s) + 6NH4Cl(aq) The product mixture is found to contain 3.741 g of barium phosphate. Using this info, calculate the percentage by mass of ammonium phosphate in the fertilizer. 2. Relevant equations % by mass = grams of fertilizer/molar mass of fertilizer x 100 (unsure if that's correct, but that's what I think it should be) 3. The attempt at a solution I started by taking the given amount of barium phosphate to find moles of ammonium phosphate. I think I need to use that to find grams of ammonium phosphate. However, I am also having difficulty trying to understand what the problem is specifying as the fertilizer. Is it the ammonium phosphate AND the barium chloride, or just the ammonium phosphate?