Why does soduim ascetate turn into ice?

Answer 1

Firstly, when sodium acetate (CH3COONa) solidifies, it does not form "ice". It just becomes solid. This happens when the sodium acetate is heated to about 100oC, then cooled below its freezing point. When a foreign substance with the same crystal structure as sodium acetate is introduced, or a nucleation centre is provided, the sodium acetate will warm up to its freezing point and freeze at its (supposed to be) freezing point.

Answer 2

Sodium acetate trihydrate is a supersaturated solution that has the ability to undergo a phase transition from liquid to solid upon activation, usually via agitation or the addition of a seed crystal. This process releases latent heat, resulting in the rapid crystallization of the solution into solid sodium acetate crystals, resembling ice.