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Since theoretical yield is the maximum measure of the product of a reactant, actual yield will always be lower as a result of human error that may occur during the reaction process, so unless the problem states specifically what the errors were I don't think we'll be questioned on the reason as to why the actual yield is lower than the theoretical one.
Yeah, I doubt you would need to know it on a case specific basis. But, it may be good to be able to describe some reasons off the top of your head so Reactant sticking to the container, instrumental errors, side rxns, etc.
I doubt that specifics are needed as to why the actual yield is less than the theoretical yield, especially since this is a "relatively" introductory chemistry class. However, it is good to know some possibilities or why in general this disparity occurs. For example, since the theoretical yield is the maximum amount of product possibly produced, occurrences like human error, unideal conditions, or slight losses to heat may lead to the difference in actual vs. theoretical. In essence, since theoretical is based purely on the equation and mathematic conversions and not disparities from reality, the actual yield is bound to practically always be less than theoretical.
Actual yield is the result of imperfections in the experiment such as contents being stuck to the sides of the test tube, therefore it is less than theoretical yield, which is the calculated maximum amount of product that can derive from the experiment.
Could actual yield ever be greater than theoretical yield? Maybe there are impurities in the reagents or the scale isn't calibrated correctly? I remember doing labs in high school where we ran into issues of actual yield vs theoretical yield when we got impossible amounts of product during experiments.
Actual yield should typically not be greater than the theoretical yield because theoretical yield is the maximum amount of product that could have been produced. However, there may be cases in your own personal experiment which may result in a higher actual yield than the theoretical yield, resulting in a percentage yield exceeding 100%. This may be due to experimental errors or human error. There may have been transfer errors, impure reactants, or maybe the limiting reagant that was provided was a solution of a higher concentration than reported.
Actual yield should generally be lower than theoretical yield; this is due to human error, etc. However, in a laboratory setting if you obtain results in which actual yield>theoretical yield, then it is likely that your sample is contaminated.
I doubt there is any question that asks to find a reason because like professor Lavelle said in class, the theoretical yield is the maximum and the actual yield will be less because of human error and the difficulty in precisely and accurately obtaining the correct yield, whether it be some solutions left on the flask when measuring or some minor calibration error.
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