Crystallization of sodium acetate, image 2 in a series of 4. When sodium acetate trihydrate (CH3COONa 3H2O) melts at 58C, it releases bound water (water of crystallization) and dissolves in it. When the solution is allowed to cool slowly, it becomes supersaturated. If a nucleation centre (ex., a small piece of solid sodium acetate, Photo 1) is formed or introduced, it causes the solution to crystallize back into solid sodium acetate trihydrate (Photos 2-4). This process is exothermic and releases heat. It found its use in consumer heating pads. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Giphotostock |
Bildgröße: | 3419 px × 5092 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |