Uses of Sodium Fluoride NaF
Sodium Fluoride NaF is a colorless bright crystal or white powder with a specific gravity of 2.25, a melting point of 993 °C and a boiling point of 1695 °C. Soluble in water, hydrofluoric acid, slightly soluble in alcohol. The aqueous solution is weakly alkaline and dissolves in hydrofluoric acid to form sodium bifluoride, which can corrode glass. poisonous!
Colorless cubic or tetragonal crystals. Sensitive to moisture. Solubility in water (g/100ml): 4 at 15°C, 4.3 at 25°C, 5 at 100°C, insoluble in ethanol. The partial hydrolysis of the aqueous solution is an alkaline reaction. The pH of the freshly prepared saturated solution was 7.4. Its aqueous solution can make glass hairy, but its dry crystals or powder can be stored in glass bottles. Relative density 2.78. Melting point 993 ℃.
Main uses of Sodium Fluoride NaF:
It is used as a phosphating accelerator in the coating industry to stabilize the phosphating solution, refine the phosphating, and improve the performance of the phosphating film. In the phosphating of aluminum and its alloys, the Al3+, which has a very harmful negative catalytic effect, is blocked, so that the phosphating can proceed smoothly. Wood preservatives, agricultural pesticides, brewing fungicides, pharmaceutical preservatives, welding fluxes, alkaline zincate galvanizing additives and enamel, paper industry, etc.
Because fluoride ions can form stable complexes with ferric ions, so that thiocyanate does not develop red color, so it is used as a masking agent for ferric ions in the laboratory.
The above is the introduction of the use of Sodium Fluoride NaF, do you all understand?