A student calculates a percentage yield of 115%. Which of the following is the most likely explanation?

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Question

A student calculates a percentage yield of 115%. Which of the following is the most likely explanation?

Accepted Answer

The product was not completely dry — Award 1 mark for identifying that water or solvent contamination increases apparent mass. A is incorrect — no reaction can exceed 100% yield due to conservation of mass. B is incorrect — catalysts do not increase yield beyond theoretical maximum. D is incorrect — this would result in lower, not higher, percentage yield.

Answer

The product was not completely dry

Answer

A catalyst was used

Answer

The reaction was very efficient

Answer

The theoretical yield was too high

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