Percent Yield  [ENDORSED]

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Lily Benitez 2G
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Percent Yield

Postby Lily Benitez 2G » Tue Oct 09, 2018 10:12 pm

I know that the equation for percent yield is Actual Yield/Theoretical Yield...but I still confused on which value is which. Can someone please explain the difference between actual and theoretical?

Patrick Cai 1L
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Re: Percent Yield

Postby Patrick Cai 1L » Tue Oct 09, 2018 10:19 pm

Theoretical is the value that you obtain from doing stoichiometric calculations and obtaining a number for the maximum possible amount of product. Actual is the value you obtain experimentally, as a result of doing the experiment in a real world setting. In such a situation, the reaction being analyzed is most likely occurring in a situation where there are side reactions also occurring and not all the reactants are utilized.

Maria Nabagala 3E
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Re: Percent Yield

Postby Maria Nabagala 3E » Tue Oct 09, 2018 10:23 pm

Actual yield is what you actually get from the reaction while theoretical yield is what you hope/expect to get from the reaction.

Francis_Nguyen3D
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Re: Percent Yield  [ENDORSED]

Postby Francis_Nguyen3D » Tue Oct 09, 2018 10:24 pm

So for a theoretical yield, it is the amount(grams) of product that you receive through calculations considering that the conditions of the experiment are perfect. One way to think about theoretical yield is the amount you calculated on paper. As for the actual yield, it is the amount(grams) of product that is measured through the actual experiment. Think of this being the amount of product you made from actually conducting an experiment. The actual yield is often less than the theoretical yield because of outside factors affecting the reaction such as reactants sticking on the sides of the beaker.
Hope this helps!

CateJensen3K
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Re: Percent Yield

Postby CateJensen3K » Tue Oct 09, 2018 11:03 pm

Usually you will be given the value for the actual yield because we are not in a lab course and then the value that you are calculating by using stoichometry is the theoretical yield.

Courtney McHargue 1I
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Re: Percent Yield

Postby Courtney McHargue 1I » Wed Oct 10, 2018 11:43 am

Actual yield is the amount of product formed when performing the reaction in real life, theoretical yield is the maximum predicted amount of that same product formed if the reaction completely uses up its limiting reactant and doesn't lose any product due to error. The actual yield will almost always be less than the theoretical, as no experiment runs completely perfectly.

Letizia Ye 4F
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: Percent Yield

Postby Letizia Ye 4F » Wed Oct 10, 2018 7:37 pm

The actual yield is like the experimental yield of the reaction, something you would get if you performed the reaction in real life. The theoretical yield is the value you get when you do your stoichiometry calculations!

leediane0916
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Re: Percent Yield

Postby leediane0916 » Wed Oct 10, 2018 8:44 pm

in these problems the actual yield should be given (because you can't conduct the experiment by yourself and figure that value out) and the theoretical yield is the amount of the product that you deduce from the given equation!

Kevin ODonnell 2B
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Re: Percent Yield

Postby Kevin ODonnell 2B » Thu Oct 11, 2018 12:10 pm

You should be given the actual yield, and have to calculate for the theoretical yield. This is because we can't calculate for the disruptions that take place during an experiement (side-rections, molecules stuck to the side of the beaker, etc). The actual yield is also done in an experiment setting. Something to also remember that may help is that actual yield will always be less than the theoretical yield.

Stephen Sirmay 1I
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Re: Percent Yield

Postby Stephen Sirmay 1I » Thu Oct 11, 2018 12:31 pm

Theoretical yield can be calculated by
1. balancing chemical equation
2. finding moles of reactant
3. use molar ratio of reactants from balanced equation to find how many moles it takes each reactant to use up the other
4. the reactant with not enough moles to use up the other is the limiting reactant
5. Use the limiting reactant to calculate the moles of product and convert those moles to grams; this is the theoretical yield

the actual yield will be given in the equation unless you carry out the experiment itself

(actual yield/theoretical yield) x 100 = percent yield

Katie Sy 1L
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Joined: Fri Sep 28, 2018 12:18 am

Re: Percent Yield

Postby Katie Sy 1L » Thu Oct 11, 2018 12:51 pm

Actual Yield is the value the problem should give you. It's the amount actually produced in the experiment. Theoretical yield is the amount you should expect to produce while using information from the balanced equation and the starting amount of the reactant.

NatBrown1I
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Joined: Fri Sep 28, 2018 12:17 am

Re: Percent Yield

Postby NatBrown1I » Sun Oct 14, 2018 11:41 pm

Actual yield is the value that the problem will give you and is the value that you would get if you were doing an experiment (which is usually less than the theoretical value).

Theoretical yield is the yield that you will need to calculate based on the mass values or molar values given to you in the problem.

yuetao4k
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Re: Percent Yield

Postby yuetao4k » Mon Oct 15, 2018 1:48 am

More often than not, the actual yield will be less than the theoretical yield because in reactions, there is always room to make error and chemical products and reactants could "escape" the experiment. The actual yield is the yield you get from conducting the experiment in real life, and the theoretical yield is the yield you calculate from given measurements on paper.

Linyu Zeng 1H
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Joined: Fri Sep 28, 2018 12:19 am

Re: Percent Yield

Postby Linyu Zeng 1H » Fri Oct 19, 2018 4:16 pm

The actual yield is the weight you actually measured in the lab (which will be given to us in tests since we can't measure it by ourselves". and the theoretical yield is what you calculate to be the weight of the products.


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