How many grams of hydrogen are needed to produce 15.0 mol of ammonia if the reaction goes to completion?

Reaction involved in present system is :  N2   +    3H2     →    2NH3

In present reaction, 1 mol of N2 react with 3 moles of H2 to generate 2 moles of NH3

Thus, 2 moles of NH3 ≡ 3 moles  of H2
Therefore, 15 moles of NH3 ≡ (3X15)/2 = 22.5 moles of H2.

We know that, 1 mole of H2 ≡ 2 g
Therefore, 22.5 moles of H2 ≡ 2 X 22.5 = 45 g

Thus, 45 g of hydrogen are needed to produce 15.0 mol of ammonia, if the reaction goes to completion

It will fall off and tip over.