Potassium hydroxide is a familiar chemical product, mainly white translucent crystalline solid. In fact, what we don't understand is that chemical products are easy to deteriorate due to their own characteristics, but it is difficult to distinguish them. At this time, we need to have a complete set of methods to detect their qualitative changes. Then, let's give you a specific explanation.
1、 Clear lime water is added to the sample. If white precipitate is formed, potassium hydroxide will deteriorate.
2、 If excessive dilute hydrochloric acid is dripped into the sample, the product will deteriorate if there are bubbles.
3、 If barium chloride is added to the sample, if white precipitate is formed, the product will deteriorate.
4、 Inspection of partial deterioration of potassium hydroxide:
1. Add excess barium chloride to precipitate completely. After the precipitate is completely static, take the supernatant into the test tube and drop colorless phenolphthalein solution. If phenolphthalein turns red, it is proved that there is NaOH.
2. If white precipitate is formed, the product is deteriorated
3. Add colorless phenolphthalein, if colorless phenolphthalein does not change color, it means complete deterioration. If the colorless phenolphthalein turns red, it means that part of it is deteriorated.
The above is about the deterioration detection method of potassium hydroxide. The product can not be used after deterioration, which seriously affects the effect of use. Through the above introduction, we found that the above detection methods are mainly carried out with the help of other chemical raw materials. Therefore, we must pay attention to safety when testing, do not put these chemical raw materials in disorder.