A hot water bag, which is transparent, and there is a small piece of iron, broke apart after the white, and then said to use hot water to boil, boil for how long? What to cook
After cooking, it will turn into a liquid and then it can be used for the first time. Put the hot water inside. You can use it again
The liquid in a warm bag is a supersaturated solution of sodium acetate (CH3COONa). Because the concentration of supersaturated solution is too high, it is not stable. When we twist the sheet of metal inside, a slight shock is enough to crystallize the solute into a stable solid. However, the process is exothermic, so warm handbags start to warm up.There is an advantage of warm handbags that can be recycled. As long as the warm hand is placed in boiling water for about 10 minutes, the condensate will be dissolved again. In the process of dissolving, the solute absorbs heat and becomes supersaturated solution again.
You must want to understand the principle of the hot bag, to understand the principle of the hot bag, we must first know what is supersaturated solution. At a certain temperature, the solubility of the solute in the solvent is unchanged. For example, the solubility of Nacl in water at room temperature is 36g/100mL water. When the concentration of the solution is equal to that of the solution, the solution is called a saturated solution. When the concentration of the solution is higher than that of the solution, the solution is called a supersaturated solution.
