supersaturated solution for rock candy

[akimhaneul]

So when making rock candy, you heat up the solvent, dissolve some sugar to make a supersaturated solution that contains more dissolved solute than a saturated solution, put in string, and slowly cool it to create crystals.

Why is it that creating rock candy can only occur under supersaturated condition and not normal saturated condition?

Anyone would like to explain the concept of supersaturated solution for me? Thanks!

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[Marrowist]

My guess would be something to do with equilibrium.

 

[aldol16]

If you take a saturated solution and add more solute or cool it, then solute will begin to crash out. It's just going to come right back out of solution as it entered and settle on the bottom. But a supersaturated solution will crystallize when you cool it. Crystallization and crashing out are not the same.