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Nitric oxide, NO, is made from the oxidation of NH3, and the reaction is represented by the equation 4NH3 + 5O2 → 4NO + 6H2O An 8.9-g sample of NH3 gives 12.0 g of NO. The percent yield of NO is .

User Kevmitch
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Answer:

≈ 177.7%

Step-by-step explanation:

To calculate the percent yield of NO, we need to compare the actual yield (what was obtained in the experiment) to the theoretical yield (what should have been obtained if the reaction had gone to completion).

First, we need to determine the theoretical yield of NO. We can do this by using stoichiometry to convert the given mass of NH3 to the expected mass of NO, based on the balanced equation. The ratio of the coefficients in the balanced equation tells us that 4 moles of NH3 produce 4 moles of NO, so the mole ratio of NH3 to NO is 1:1. Therefore, the mass of NO that should be produced is:

12.0 g NO = (8.9 g NH3) × (1 mole NO / 4 moles NH3) × (30.01 g NO / 1 mole NO)

where we have used the molar mass of NO (30.01 g/mol) to convert from moles of NO to grams of NO. Evaluating this expression gives:

12.0 g NO = 6.748 g NO

So, the theoretical yield of NO is 6.748 g.

To calculate the percent yield, we use the following formula:

percent yield = (actual yield / theoretical yield) × 100%

Substituting the given values, we get:

percent yield = (12.0 g / 6.748 g) × 100% ≈ 177.7%

This result suggests that the actual yield is greater than the theoretical yield, which is not possible. The most likely explanation is that there was an error in the experiment, such as incomplete reaction, loss of product during handling, or inaccurate measurement of the masses. Therefore, we should check the experimental procedure and repeat the experiment to obtain a more reliable result.

User Tuana
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