|MadSci Network: Chemistry|
There are a few tricky points in this calculation. First and most important, ammonia is a gaseous species; the "ammonia" you most likely talk about an aqueous solution that should be called ammonia solution for distinction. Commercially available solutions are in the range of 22-28% of ammonia in water. This is also about the solubility limit of ammonia in water, if you increase it, the ammonia will gas out. In addition, you mixed up the molar weights of ammonia and formic acid in your calculations. The easiest way to resolve the problem will be to do the calculations again. The densities should be considered, as they are significantly different from 1, with the exception of the final solution. Ammonia, NH3, 17 g/mol Ammonia solution, 28%, Density = 0.9 Formic acid, HCOOH, 46 g/mol, Density = 1.2, Ammonia solution: 2 ml * 0.9 g/ml = 1.8 g Ammonia: 1.8 g *0.28 = 0.50 g 0.5 g / 17 g/mol = 0.29 mol Formic acid: 2.5 ml * 1.2 g/ml = 3.05 g; 3.05g / 46 g/mol = 0.66 mol Considering that ammonia is the limiting reactant: Ammonium formate: 0.29 mol * 63 g/mol = 1.85 g 1.85 g / 2000 g = 0.00093 The final solution is 0.093% in 2000 ml of water. I guess you could call it a 0.1% ammonium formate solution.
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