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A student isolated 25 g of a compound from a procedure that should theoretically yield 81 g. What is the percent yield?
A25%
B31%
C56%
D324%
Answer & Solution
Correct answer: B. 31%
1. Percent yield is the actual yield divided by the theoretical yield, times 100.
2. Here the actual yield is 25 g and the theoretical yield is 81 g.
3. Dividing gives 25 divided by 81, which is 0.3086.
4. Multiplying by 100 gives 30.86%, that is about 31%.
5. Subtracting the masses to get 56 g is a different quantity and not a percent yield.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 4 "Stoichiometry of Chemical Reactions", section 4.4 Reaction Yields_
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