Why is it important that there be no gaps around the edges of the filter paper during a vacuum filtration? explain your reasoning?

Gaps around the edges would permit solids from coming through with the solvent that is being extracted. Having a complete seal would keep all solids on the filter paper, so it can be collected for further purification.

Answer(d) unstable compounds that convert to acetals in the presence of alcohol and an acid; (b) semiacetals produced by alcohol subtraction from ketone;