[Note]
1. Hot solution After cooling solute Precipitation in the form of crystal from solution is called crystal 。 2. The above conversion conditions are suitable for most solid substances, because the maximum amount of most solid substances dissolved in a certain amount of water increases with the increase of temperature.
3. The maximum amount of hydrated lime dissolved in a certain amount of water decreases with the increase of temperature. Therefore, if the unsaturated solution of hydrated lime is converted into saturated solution, the temperature should be increased when changing the temperature; If the saturated solution is converted into unsaturated solution, the method of lowering the temperature or increasing the solvent can be adopted.
4 Specify "a certain temperature" and "a certain amount of solvent", because by changing the amount or temperature of solvent, saturated solution and unsaturated solution can be converted to each other.
5 It should be clear that the saturated solution or unsaturated solution of "certain substance", such as the solution that can no longer dissolve NaCl under certain conditions, may also dissolve sucrose. For sucrose, this solution is an unsaturated solution, so it must be specified which solute is the saturated solution or unsaturated solution.
The saturated solution and unsaturated solution of a solute can be transformed into each other, and the process can be expressed as follows:
Conversion relationship between unsaturated solution and saturated solution * calcium hydroxide Change during solution conversion temperature And general rules contrary.
