Ammonia can be produced in a two-step process. First, nitrogen reacts with red-hot magnesium to form magnesium nitride. Then magnesium nitride reacts with water to form magnesium hydroxide and ammonia.

A. Write each balanced chemical reaction.
B. How many grams of magnesium would we have to start with to prepare 15.0 grams of ammonia?

A. 3Mg(s) + N2(g) --> Mg3N2(s)
Mg3N2(s) + 6H2O --> 3Mg(OH)2(aq) + 2NH3(aq)

B. 15.0gNH3 x (1moleNH3 / 17.03056gNH3) x (1moleMg3N2 / 2molesNH3) x (100.92848gMg3N2 / 1moleMg3N2) = 54.0gMg3N2

54.0gMg3N2 x (1moleMg3N2 / 100.92848gMg3N2) x (3moleMg / 1moleMg3N2) x (24.3050gMg / 1moleMg) = 39.0gMg

Is this right?