Crystallisation
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What this model shows
One prepared copper(II) sulfate solution, and then its filtrate. The steps show what happens, not exact numbers: no real temperature, time, crystal size or amount, and the waits are shortened.
Copper(II) sulfate is more soluble in hot water than in cold, so a concentrated solution forms crystals on cooling. Other solutes can behave differently. The rod test is a quick sign of when to stop heating; it does not measure exactly how saturated the hot solution is.
The close-up in the card is schematic: circles for water and squares for dissolved salt, not real particles or counts. The water inside the hydrated crystals is not shown. Blotting removes solution from the crystals’ surfaces; the water of crystallisation stays inside them.
Never taste laboratory samples. Real heating and copper(II) sulfate need a teacher-approved safety procedure.
With reduced motion, each step finishes at once.
Select a piece of equipment, on the bench or here, to read about it in the card.