For the balanced chemical reaction $N_2+3H_2\to 2N_1{H}_3$, what is the mole ratio of $N_1{H}_3$ to $N_2$?

• A. $\frac{1 \mathrm{mol} N_1{H}_3}{2 \mathrm{mol} N_2}$
• B. $\frac{3 \mathrm{mol} N_1{H}_3}{1 \mathrm{mol} N_2}$
• C. $\frac{1 \mathrm{mol} N_1{H}_3}{3 \mathrm{mol} N_2}$
• D. $\frac{2 \mathrm{mol} N_1{H}_3}{1 \mathrm{mol} N_2}$

Answer: (D)