What is the principle involved in filtration and what impurities may be removed by this?

Question

What is the principle involved in filtration and what impurities may be removed by this?

Answer 1

it is a matter of size

the filter has a porosity size that lets smaller particles pass through, while large size particles are retained

dissolved materials readily pass through the porosity of filter paper, while most precipitates will not

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& with respect to your decolorization question,...

since you are also asking questions about filtering, ....

if you were referring to using decolorizing charcoal to help purify before filtering,....

the colorful material adsorbs onto the charcoal, effectively removing it from your product