The molar mass refers to the mass of 1 mole particles, that is, the sum of the masses of the Aff Gadereau constant (about 6.02 * 10 to the 23rd power, that is, 6.02 times 10 to the 23rd power). In grams, it is numerically equal to the relative atomic mass or relative molecular mass of particles. The relative molecular mass of sodium sulfite is 126, so its molar mass is126g/mol (126g/mol).
Chemical properties:
Its aqueous solution is alkaline, strong oxidant, reducible, gradually oxidized in air, and its surface becomes sodium nitrate, which can also be oxidized by oxidant when heated above 320℃. When it decomposes with weak acid, it will release brown nitrogen dioxide gas;
Contact with organic matter and reducing agent can cause explosion or combustion, and release toxic and irritating nitrogen oxide gas; It can also be oxidized when it meets strong oxidants, especially ammonium salts, such as ammonium nitrate and ammonium persulfate, which can interact at room temperature to produce high heat and cause combustible combustion.
Precautions:
Sodium nitrite is an industrial salt. Although it is similar to salt and sodium chloride, it is toxic and inedible. Sodium nitrite is highly toxic. People may have poisoning symptoms if they eat 0.2 g to 0.5 g, and they may die if they eat 3 g by mistake once.
Sodium nitrite poisoning is characterized by cyanosis, and its symptoms and signs include headache, dizziness, fatigue, chest tightness, shortness of breath, palpitation, nausea, vomiting, abdominal pain, diarrhea, cyanosis of lips, nails, skin and mucous membranes, even convulsions and coma, and even life-threatening in severe cases.
Sodium nitrite is widely used in curing meat. If there is cyanosis of methemoglobin, methylene blue can be used to reduce methemoglobin. The reason why sodium nitrite is poisoned by mistake is because the iron contained in hemoglobin in human body is ferrous, which can combine with oxygen and transport oxygen to all parts of the body with blood circulation.
When sodium nitrite is eaten by mistake, there will be a chemical reaction in the blood, which will convert hemoglobin into iron hemoglobin. Hemoglobin of ferric iron can't carry oxygen, so it causes hypoxia poisoning in human body. Therefore, eating sodium nitrite by mistake is very harmful to health.
As a food additive, it is produced according to GB 1907 and added according to GB2760. The maximum dosage in meat is 0. 15g/kg, and the residue of sodium nitrite in meat should not exceed 0.05g/kg；. . Meat products shall not exceed 0.03g/.