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{ }*\text{ }\frac{1\text{ mol H}_2}{2\text{ g H}_2}\text{ }*\frac{2\text{ mol NH}_3{}}{3\text{ mol H}_2}{}*\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}}*100\%\text{ }`
`\%\text{ yield = }\frac{\text{ 17.5 g}}{\text{ 22.6}}*100\%\text{ = 77.4 }\%`

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