Ammonium hydrogen fluoride, also known as ammonium fluoride. Its properties are as follows:
1. Appearance: Ammonium hydrogen fluoride is a colorless crystalline solid or granular powder.
2. Solubility: Ammonium hydrogen fluoride has good solubility in water and the solution is weakly acidic.
3. Acidity: Ammonium hydrogen fluoride can release hydrogen fluoride gas in humid air.
The use of ammonium hydrogen fluoride:
1. As an etchant and delamination agent: Ammonium hydrogen fluoride has strong etching and stain removal abilities and is commonly used in etching processes in semiconductor manufacturing and glass industry.
2. Preparation of metal fluorides: Ammonium hydrogen fluoride can be used to prepare fluoride compounds of other metals, such as sodium fluoride, aluminum fluoride, etc.
3. Chemical analysis: Ammonium hydrogen fluoride can be used as an analytical reagent to detect the presence and concentration of certain metal ions.
4. Laboratory use: Ammonium hydrogen fluoride can be used as a reagent in the laboratory, such as an indicator for acid-base titration.
There are generally two methods for producing ammonium hydrogen fluoride:
1. Reaction of sodium fluoride and ammonium sulfate: Dissolve sodium fluoride in water and then react with ammonium sulfate to obtain ammonium hydrogen fluoride through crystallization, washing, and other steps.
2. Direct fluorination reaction: reacting ammonium salts with fluorides, such as [NH4] HSO4, with sodium fluoride (NaF) to obtain ammonium hydrogen fluoride.
Safety information for ammonium hydrogen fluoride:
2. Inhalation of ammonium hydrogen fluoride dust may cause irritation to the throat and respiratory tract. Inhalation of dust should be avoided and a well ventilated environment should be maintained.
3. Ammonium hydrogen fluoride should be stored in a dry, sealed, and cool place, away from sources of fire and oxidants.
4. When using ammonium hydrogen fluoride, appropriate personal protective equipment such as gloves, protective goggles, and masks should be worn to ensure safe operation.