Explain why it is important that there be no gaps around the edges of the filter paper during a vacuum filtration

Vacuum filtration is more efficient and faster than filtration by the gravity method. But the set up of the vacuum filtration must be precise. Vacuum filtration is done under very reduced pressure hence there should be no gaps around the edges of the filter paper.   For a vacuum to be effective there must be no hole or gap in the equipment. Under vacuum conditions air is removed and the pressure is lowered. If there is gap then air would be continuously supplied and it would be difficult to remove air completely.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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