Question

When 170 g $N{H}_3$ (M = 17) decomposes, how many grams of $N_2$ and $H_2$ is produced?

• A. 140 g, 140 g
• B. 30 g, 30 g
• C. 140 g, 30 g
• D. 40 g, 30 g

Answer 1

Answer: (C)

140 g, 30 g

$2N{H}_3⟶N_2+3H_2$

Moles of ammonia=$\frac{170}{17}$=10

2 moles of ammonia will produce 1 mole of nitrogen and 3 moles of hydrogen.

10 moles of ammonia will produce 5 moles of nitrogen 15 moles of hydrogen.

5 moles of nitrogen=$5\times 28=140g$

15 moles of hydrogen=$15\times 2=30g$