Question: how many grams of hydrogen are required to react with 50.0 g of nitrogen to form ammonia?
Answer: The mass (m) of hydrogen is: [ m=5.357142857×2.0 ] = 10.7 grams. Note that: this answer is rounded to 3 significant figures. Therefore, 10.7 grams of Hydrogen are necessary to fully react with 50.0 grams of Nitrogen.