Why is gravity filtration rather than suction filtration used to remove suspended impurities and charcoal from

Question

(question continued) "from a hot solution?"

from a hot solution?

Answer 1

Under suction a hot solution is likely to boil. Then you'd be sucking lots of vapor rather than liquid. By evaporating the liquid, this would also decrease the solution temperature and increase the concentration of the solute, which could cause some of the solute to precipitate out of solution (which may or may not be desirable).