[elron]

ok for whatever reason this question on my study guide is killin me.  I think it's mainly because I'm so burnt out from studying but if anyone could help me explain how to get the answer I will do anything(pm me your paypal or venmo for a donation, i really appreciate your time). 

7.0 g nitrogen monoxide (NO) is reacted with 12.0 g fluorine gas (F₂) to produce nitrogen fluoride and oxygen 2NO + 3F₂  2NF₃ + O₂.  What is the percent yield if 11.0g O₂ is experimentally produced?

note: the answer according to the study guide answer key is 30.6% but what I really need to understand is how to get to that answer.  Thanks!

[chenbeier]

You have to calculate the mole of the NO . You  can see that 2 mole NO correspond to 1 mole O₂.

Then you compare the mole of 7 g NO how much it correspond to the mole of oxygen. But the given number never can obtain 11 g oxygen.

The same thing you can do by using the flourine.  3 mole F₂ to 1 mole O₂

In both cases 11 g is not possible.

[Enthalpy]

I don't see neither how 7g NO should produce 11g O₂.

[Traumatic Acid]

I don't see neither how 7g NO should produce 11g O₂.

Nope, in fact 7 grams of NO equates to 0.23 mols. This means that the most O that can be produced is 0.23 mols.

But in your equation it states 2 mols of NO, which yeilds 2 mols of O, or one mole of O2.
One mole of O2 has a mass of 32 grams. The fact that you only got 11 grams of O2 and not 32 indicates a loss. So calculate the percent yeild of O2

Actual yeild / theoretical yeild
= 11/32 = 0.34 x 100 = 34%
Not the exact same answer so I suspect the teacher was using more precise molar masses.
I'm not sure what's with the 7 grams of No, when it states in the equation that 2 moles were used. That's just sloppy stoichiometry 

[Borek]

Not the exact same answer so I suspect the teacher was using more precise molar masses.
I'm not sure what's with the 7 grams of No, when it states in the equation that 2 moles were used. That's just sloppy stoichiometry 

No, that is not a sloppy stoichiometry, that's just a sign you don't understand the difference between balanced reaction and stoichiometry of a particular process. High school error. Not kind of a mistake I would expect from someone stating

I'm currently a second year Bachelor of Science student majoring in Chemistry and minoring in Biochemistry.