Potassium hydroxide and sodium hydroxide are bound to deliquesce under ordinary laboratory conditions. Deliquescence is faster in the state of crushing, so it is impossible to weigh accurately. Therefore, if you want to crush flake potassium hydroxide just for accurate weighing under ordinary conditions, you don't have to consider it.
方法 #1 在干燥氣氛下操作，最簡單的就是在惰性氣體保護下的手套箱或者手套袋里稱量；
The method #1 is to operate in a dry atmosphere. The simplest way is to weigh in a glove box or glove bag under the protection of inert gas;
#2 considering that potassium hydroxide is generally used in solution, the approximate amount can be weighed and dissolved in the corresponding solvent, and then the real concentration can be determined by titration. The specific process of titration needs to be determined according to the type of solvent, and a large amount of relevant information can be obtained on the Internet. In addition, pay attention to sealing the container to protect the solution from being damaged by carbon dioxide in the air;
Plan B: if you think the error of less than 10% is acceptable (I can generally catch up with my feet), make a spatula and mash it (be careful not to inhale potassium hydroxide powder, which is very choking) and then weigh it quickly.