2 NH3 + 3 CuO --> 3 Cu + N2 + 3 H2O In the above equation how many moles of N2 can be made when 165.7 grams of CuO are consumed?

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

Find the mass in grams of 1.37x1020 particles of h3po4

Which of the following is most likely true about water in chemical systems? a) water dissolves nonpolar ionic compounds. b) water dissociates ionic compounds. c) water dissociates covalent molecules. d) water dissolves nonpolar covalent substances.