White to light yellow granular, rod or powder. Hygroscopic. Heat to over 320 ℃ for decomposition. Soluble in 1.5 parts of cold water, 0.6 parts of boiling water, slightly soluble in ethanol, the aqueous solution is alkaline. Relative density 2.17. Melting point 271 ℃.

Chemical property

It is a strong oxidant with reducibility,

Sodium nitrite

In the air, it will gradually oxidize, and the surface will become sodium nitrate, which can also be oxidized by oxidants; in case of weak acid decomposition, it will release Brown nitrogen dioxide gas; in contact with organic matter and reducing agent, it can cause explosion or combustion, and release toxic and irritant nitrogen oxide gas; in case of strong oxidant, it can also be oxidized, especially ammonium salt, such as ammonium nitrate, ammonium persulfate, etc. at room temperature, it can interact with each other Phase action produces high heat, which causes combustion of combustibles. It is oxidable and can burn and explode when contacting with organic matters, and emit toxic and irritant nitrogen peroxide and nitrogen oxide gas.

Sodium nitrite is toxic, with a median lethal dose (rat, oral) of 180mg / kg [1]. It is said that sodium nitrite is a carcinogen, but in fact, sodium nitrite is not a carcinogen. What causes cancer is the nitrosamine generated by sodium nitrite under certain conditions. In the molecule of sodium nitrite, the valence of nitrogen is + 3. It is a kind of intermediate complex state, which has both reducibility and oxidizability. For example, Ki can be oxidized to iodine in acid solution.