Which of the following statements is a reasonable explanation for why a percent yield may be less than 100%

Question

for the synthesis of the alum, select all that apply.
a) The aluminium foil did not completely react
b) Some alum sample remained in the beaker and was not transferred to the filter paper
c) The alum sample was not dried completely in the oven
d) The aluminium foil had a large amount of non aluminium impurities

Answer 1

I would go with a and b.
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