Its a tightly-packed particles gain energy, allowing them to move more freely.
Drift velocity is equal to displacement of the moving object per unit time. The SI unit for displacement is meters while that of time is second. Hence the derived SI unit of velocity is meter per second. This also applies to electron mobility which relates to the displacement per unit time of a moving electron
I would go with salt in ocean water as when you heat it and the water begins to evaporate it will leave the salt behind
Also water in mud as the water would evaporate and leave the mud residue behind
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BRAINLIEST IF HELPED