制服丝袜人妻日韩在线无码,制服丝袜人妻日韩在线无码,制服丝袜第一页AV天堂
 
           Potassium fluoride,anhydrous
           Potassium fluoride,extra pure
           Potassium fluoride,Granular
           Silicon Dioxide
           Hydrofluoric acid
           Synthetic Cryolite
           Potassium Fluoaluminate
           Ammonium bifluoride
           Potassium Bifluoride
           Aluminium fluoride
           Sodium fluoride
           Fluorosilicic Acid
           More
 
  News Center

Hydrofluoric acid is considered to react with silica or silicate to form gaseous material, silicon tetrafluoride (SiF4), which reacts with silica or silicate to form gaseous material. The reaction of the chemical equation is:

SiO2 + 4HF = SiF4 + 2H2O,

CaSiO3 + 6HF = CaF2 + SiF4+ 3H2O.

Hydrofluoric acid added to the glass, the solution turbidity and a flocculent precipitate generated, while a small amount of white mist in the solution produced.

A small amount of white mist is hydrofluoric acid dissolved in water vapor generated acid mist. The main basis is as follows:

Inorganic hydrolysis is mainly affected by the following three factors: ion (atomic) radius and the number of charged charge; For SiF4, although the Si-F bond energy (565 kJ /mol) is larger than the bond energy of the C-F bond (485 kJ /mol), Si-F4 does not decompose at 1273 K, but Si-F4 is readily hydrolysable. The reason is that the radius of silicon atoms is larger, both 3s and 3p orbitals can form covalent bonds, and 3d empty orbitals can accept water molecules in the lone pair of electrons to form coordination bonds, thereby weakening the role of silicon and fluorine force, so that Si-F bond fracture. Therefore, Si-F4 is easily hydrolyzed and can not be present in water.

制服丝袜人妻日韩在线无码,制服丝袜人妻日韩在线无码,制服丝袜第一页AV天堂