why did you have to collect nearly 50 mL of distillate to recover all of the ethanol in the simple distillation while fractional distillation recovers a similar amount of ethanol but with a much lower volume

Fractional distillation is MORE EFFICIENT than simple distillation when used to separate a mixture into its various constituents.

Explanation:

Simple distillation involves differences in boiling points of liquids. A mixture of any number of liquids could be separated as long as they boil at different temperatures. The process involves heating the mixture of liquids until the more volatile liquid ( that is, the one with the lower boiling point) changes to vapour. The vapour is cooled by passing it through a condenser and collected in a liquid form known as distillate.

Simple distillation is LESS EFFICIENT than fractional distillation because the surface area inside the column is small. This makes the distillation process faster and not allowing enough time for the volatile liquids to escape. Large quantity of distillate would be obtained due presence of traces of other liquids found in the original mixture.

Fractional distillation is a method used in the separation of miscible liquids with close boiling points. Here, fractionating column is introduced between the flask and the condenser. The liquid with the higher boiling point (less volatile) condenses and falls back into the flask. While the one with the lower boiling point (more volatile) distils over into the condenser and collected as the first distillate.

Fractional distillation is MORE EFFICIENT than simple distillation because the fractionating column provide "theoretical plates" on which the vapors can condense and then re-evaporate, and re-condense, essentially distilling the mixture many times over. Therefore the quantity of distillate obtained from fractional distillation will be reduced as there would be no traces of other liquids from the mixture except pure ethanol.