hey there!:
Colloidal dispersions are formed by larger molecules or clusters of them, such as proteins in water, for example. The particles, although considerably larger than those of a solution, cannot yet be seen with the naked eye. Only in some special microscopes called Ultramicroscópios. They may decant, if centrifuged properly, or be filtered if the filter is sufficiently thin.A suspension is a dispersion of coarse particles in some dispersant, like sand or land in water. The particles of sand or dirt can easily be seen with the naked eye or with the aid of a magnifying glass and also be filtered or decanted.The difference between the two is in the size of the scattered particles.
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