Yes. Under standard atmospheric pressure, when pure water has just reached 100 degrees, if all heat exchange is stopped (i.e. heating is stopped and adiabatic is entered) and heat is no longer transported, the water will not boil. The boiling water must overcome the steam pressure, and there are two ways to do this: 1. Continue heating. 2. Provide a "condensation core" for water ready to boil, allowing water molecules to attach to this core and form bubbles that are boiling. If you add salt to hot water, when the salt particles are not dissolved, they act as condensation nuclei, causing the water to boil more quickly. What is said above makes sense and I will provide another explanation.
It will stop.
Rechargeable hand warmers are divided into two types: electrode type and water and electricity separation type.
The plMost rechargeable hand warmers are electrode type and the water inside contains a certain amount of salt and has been prepared. If you change it, you will have to adjust the salt water yourself, which will be very inconvenient, so it is recommended not to change it. If ordinary people change this water, there is a good chance that the hot water bottle will be charged.
If it is a separate water and electricity type, it can usually be replaced, but pay attention to the exhaust