Question

For the following reaction, 3.98 grams of hydrogen gas are mixed with excess nitrogen gas . The reaction yields 17.5 grams of ammonia .

Answer 1

$\text{ N}_2\text{ + 3H}_2\text{ }\rightarrow\text{ 2NH}_3$

Theoretical yield

$3.98\text{ g H}_2\text{ }\times\text{ }\frac{1\text{ mol H}_2}{2\text{ g H}_2}\text{ }\times\frac{2\text{ mol NH}_3{}}{3\text{ mol H}_2}{}\times\frac{17\text{ g NH}_3}{1\text{ mol NH}_3}=22.6\text{ g NH}_3$

Percent yield

$\%\text{ yield = }\frac{\text{ actual yield}}{\text{ theoretical yield}}\times100\%\text{ }$$\%\text{ yield = }\frac{\text{ 17.5 g}}{\text{ 22.6}}\times100\%\text{ = 77.4 }\%$

The answer is theoretical yield = 22.6 grams of ammonia and percent yield = 77.4 %