In general, it is recommended that you do not discard any solid or solution until it is clear that the fraction is definitely waste. It is much easier to store a solid or solution until the end of an experiment, than it is to start over and re-prepare the solid or solution.
Solids
When the solid is dry, use a glass rod or rubber policeman to quantitatively transfer the solid to a weighing vessel. Avoid touching the solid, wear gloves if necessary. DO NOT use a metal spatula to scrape the solid from the paper or fritted glass. Instead, use a glass rod or rubber policeman to quantitatively transfer the solid.
Check to see if the solid is dry by weighing the solid every five minutes (or longer if reasonable) until a constant weight is achieved. In between weighings, spread the solid into a thin layer and allow the solid to stand. If a dessicator is available, place the solid in the dessicator during the drying period.
Filtrates
When all of the liquid has passed through the filtering media, remove the funnel and transfer the filtrate to a new container. DO NOT attempt to boil the solvent away from the filtrate in the side-arm flask. Instead, use a distillation apparatus or a beaker (use a beaker only if specifically instructed to do so) to remove the solvent.
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