Dinitrogen and dihydrogen react with each other to produce ammonia according to the following chemical equation:


(i) Calculate the mass of ammonia produced if 2.00 × 103 g dinitrogen reacts with 1.00 ×103 g of dihydrogen.


(ii) Will any of the two reactants remain unreacted?


(iii) If yes, which one and what would be its mass?

The reaction given in the question is not balanced.

Balancing the above chemical reaction:


N2 + 3H2 2NH3


(i) Finding mass of NH3 produced:


Atomic Mass of Hydrogen = 1g


Atomic Mass of Nitrogen = 14g


Molecular Mass of Nitrogen = 14 + 3


= 17 g


From the chemical equation we observe that 28g of nitrogen react with 6g of hydrogen to give 34g of ammonia


Therefore 1 mole of dinitrogen reacts with 3 moles dihydrogen to give 2 moles of ammonia.


Therefore, amount of dihydrogen required to react with 2000g of dinitrogen = [6×2000]/28


= 12000/28


= 428.57g


Therefore, 2000g of dinitrogen will produce = [34×2000]/28


= 68000/28


= 2428.57g of Ammonia


Therefore 2428.57g of ammonia is produce when 2000g of dinitrogen is used.


(ii) Since dinitrogen is present in lesser amount, it is the limiting reagent and dihydrogen is the excess reagent and hence H2 will be left unreacted.


(iii) Mass of dihydrogen left unreacted = 1000 – 428.57


= 571.43g


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