GCSE, help :( Watch

HidingMyFailure
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Nitrogen reacts with hydrogen to make ammonia.
N2 + 3H2 ⇌ 2NH3
a. Calculate the theoretical yield of ammonia, NH3, that can be produced by reacting 90 tonnes of hydrogen with an excess nitrogen
b. The actual yield of ammonia is 120 tonnes. Calculate the percentage yield of ammonia

would appreciate any help because triple chemistry is absolutely kicking my arse
Last edited by HidingMyFailure; 4 weeks ago
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Tamimur
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If you want some triple help message me on discord if you have it ShadyNya#5236
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Kian Stevens
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a.) If nitrogen is in excess, then theoretically, the entire 90 tonnes (90x106 g = 45x106 moles) of hydrogen will react to form ammonia. But how much ammonia? Well, use stoichiometry. The ratio of hydrogen to ammonia is 2:3. This theoretically means that \frac{2}{3} moles of ammonia will be formed, which is equal to 30x106 moles of ammonia. This corresponds to a theoretical ammoniacal yield of 510 tonnes.

b.) Percentage yield is just the ratio of how much product is actually formed to how much would theoretically be formed, summed up in the equation: \frac{actual * 100}{theoretical}. This equation works with both masses and moles, so it's up to you which you choose. Using masses, the yield is \frac{120 * 100}{510} = 23.5%. Using moles, the yield is \frac{7.06 * 100}{30} = 23.5%. Hence, it's up to you which you use.
Last edited by Kian Stevens; 4 weeks ago
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