How to determine the impurities in potassium hydroxide2020-06-28 11:36
Potassium hydroxide is used in many cosmetics fields, so the quality requirements when using it are relatively high. If there are many other ingredients in it, then it is used. At that time, it is likely that the expected use effect may not be achieved. Even if it is used in cosmetics, it may be harmful to the skin. How should we determine the amount of impurities contained in it when using it?
1. First, use a balance scale to take out the accurate sample weight of 1.5-2.0g, then place it in a beaker of 250ml, and add distilled water to dissolve it. After the dissolution is complete, it can be imported to the same size capacity In the bottle, and when the water is dissolved to 250ml, you can stop adding water.
2. Pour the dissolved solution into three conical flasks and add two drops of phenolphthalein indicator. Then add the hydrochloric acid solution dropwise until the potassium hydroxide solution changes from red to no color, then stop adding, then record the volume of used hydrochloric acid and add 2 drops of methyl orange indicator, using the same hydrochloric acid standard The solution is titrated until the solution turns orange and the addition can be stopped.
3. Then record the volume of the hydrochloric acid solution added twice, and then calculate the impurity content in the product based on this.
The method described above is to determine the content of impurities in potassium hydroxide. When we use it, we must know what impurities are contained in it, and whether it will cause a negative impact on our normal use, so this also We are required to choose good quality when making a purchase.