Time of issue:2020-09-18 09:54:26
Time of issue:2020-09-18 09:54:59
Time of issue:2020-09-18 09:55:24
Time of issue:2020-09-18 10:07:52
Five water sodium selenite
Editing Method neutralized with sodium hydroxide and sodium selenite selenite to generate:
2NaOH + H2SeO3 = Na2SeO3 + 2H2O
By the amount of the chemical reaction required for the above, the sodium carbonate solution containing no measure exactly the selenite mixed with concentrated acid solution. At room temperature the solution was placed under vacuum over anhydrous calcium chloride and evaporated. Because this is easy to form a supersaturated solution of salts, when available in the final glass rod was evaporated to wall friction to promote crystallization. In order to obtain large crystals can be precipitated as a microcrystalline seed crystals were added to a saturated solution, followed by evaporation was continued. Glass frit funnel crystalline drained, placed no desiccant dessicator attached to the crystal surface to remove moisture, can be obtained Na2SeO3 · 5H2O.
The main purpose
Editor for the prevention and control of Keshan disease has achieved remarkable results in the prevention of livestock selenium deficiency is also effective. Alkaloid used as a test, seed germination agents, but also for the red glass, glazed formulation. With its prevention and control of Keshan disease achieved remarkable results in the prevention of livestock selenium deficiency is also effective.
Edit Risk Phrases
R23: Toxic by inhalation Toxic by inhalation.
R28:. Very toxic if swallowed Very toxic if swallowed.
R31: Contact with acids liberates toxic gas in case of acid release toxic gases.
R43:. May cause sensitization by skin contact May cause sensitization by skin contact.
R51 / 53:. Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.