If 14 kg of nitrogen yields 23 kg of nitrogen dioxide, then the percent yield for the reaction is ________. N₂ + 2 O₂ → 2 NO₂

Question

Quizplus · Accepted Answer

To find the percent yield, we need to calculate the actual yield (the amount of nitrogen dioxide produced) and divide it by the theoretical yield (the amount that should have been produced if all the nitrogen reacted). 
The balanced equation tells us that 1 mole of nitrogen reacts to form 2 moles of nitrogen dioxide. 
First, we need to convert the given mass of nitrogen to moles:
14 kg N₂ x (1 mole N₂/28.02 kg N₂) = 0.499 mol N₂

According to the balanced equation, 0.499 moles of nitrogen would react to give 0.998 moles of nitrogen dioxide. 
The mass of this amount of nitrogen dioxide is:
0.998 mol NO₂ x (46.01 g NO₂/1 mol NO₂) = 45.33 g NO₂

However, the problem tells us that 23 kg (or 23,000 g) of nitrogen dioxide were actually produced.

So the percent yield is:
(actual yield/theoretical yield) x 100%
= (45.33 g NO₂ / 23,000 g NO₂) x 100%
= 0.197 x 100%
= 19.7%
And since the answer choices are in whole numbers, the closest answer to 19.7% is B) 50%.

If 14 Kg of Nitrogen Yields 23 Kg of Nitrogen