## Chemistry 10th Edition

(a) $N_2 + 3H_2 -- \gt 2NH_3$ (b) 450. $N_2$ molecules. (c) 300. $NH_3$ molecules.
(a) Balance the equation: $N_2 + H_2 -- \gt NH_3$ - Balance $N$: The coefficient for nitrogen on the reactants is "2" from $N_2$, so we should put that number as the coefficient of $NH_3$: $N_2 + H_2 -- \gt 2NH_3$ - Balance $H$: There is a total of 6 hydrogens on the products, so we should put a "$\frac{6}{2}$" (which is 3) as the coefficient of $H_2$; $N_2 + 3H_2 -- \gt 2NH_3$ ------ Use the coefficients as conversion factors: (b) According to the balanced equation, the ratio of nitrogen molecules to hydrogen molecules is 1:3, so: 150. $N_2$ $\times \frac{3H_2}{1N_2} = 450. H_2$ (c) According to the balanced equation, the ratio of nitrogen molecules to ammonia is 1:2, so: 150. $N_2$ $\times \frac{2NH_3}{1N_2} = 300. NH_3$