氢氧化钠 NaOH固体溶于水放热；又称烧碱、火碱、苛性钠，是常见的、重要的碱，英文名称sodiun hydroxide（别名Caustic soda）。 化学式NaOH 式量40.01。密度2.130克/厘米3，熔点318.4℃，沸点1390℃。纯的无水氢氧化钠为白色半透明，结晶状固体。
NaOH solid solution in water exothermic; also known as caustic soda, caustic soda, caustic soda, is a common and important alkali, English name sodium hydroxide (alias calcium soda). The amount of NaOH is 40.01. 130 g / cm3, melting point 318. 4 ℃, boiling point 1390 ℃. Pure anhydrous sodium hydroxide is white, translucent, crystalline solid.
氢氧化钠极易溶于水，溶解度随温度的升高而增大，溶解时能放出大量的热。它的水溶液有涩味和滑腻感，溶液呈强碱性，具备。氢氧化钠的用途十分广泛，在化学实验中，除了用做试剂以外，由于它有很强的吸湿性，还可用做碱性干燥剂。烧碱在国民经济中有广泛应用，许多工业部门都需要烧碱。使用烧碱最多的部门是化学药品的制造，其次是造纸、炼铝、炼钨、人造丝、人造棉和肥皂制造业。
Sodium hydroxide is easily soluble in water, and its solubility increases with the increase of temperature. When it dissolves, it can release a lot of heat. Its aqueous solution is astringent and greasy, the solution is strong alkaline, with good taste. Sodium hydroxide is widely used in chemical experiments. In addition to being used as a reagent, it can also be used as an alkaline desiccant because of its strong hygroscopicity. Caustic soda is widely used in the national economy, many industrial sectors need caustic soda. The sectors that use caustic soda most are chemical manufacturing, followed by papermaking, aluminum smelting, tungsten smelting, rayon, artificial cotton and soap manufacturing.

另外，在生产染料、塑料、药剂及有机中间体，旧橡胶的再生，制金属钠、水的电解以及无机盐生产中，制取硼砂、铬盐、锰酸盐、磷酸盐等，也要使用大量的烧碱。工业用氢氧化钠应。>>在工业上，氢氧化钠通常称为烧碱，或叫火碱、苛性钠。
In addition, in the production of dyes, plastics, chemicals and organic intermediates, the regeneration of old rubber, the electrolysis of metal sodium and water, and the production of inorganic salts, a large amount of caustic soda is also used in the production of borax, chromate, manganate, phosphate, etc. Sodium hydroxide for industrial use should be used. >>In industry, sodium hydroxide is usually called caustic soda, or caustic soda.
这是因为较浓的氢氧化钠溶液溅到皮肤上，会腐蚀表皮，造成烧伤。它对蛋白质有溶解作用，有强烈刺激性和腐蚀性。用0.02%溶液滴入兔眼，可引起角膜上皮损伤。小鼠腹腔内LD50: 40 mg/kg，兔经口LDLo: 500 mg/kg。粉尘刺激眼和呼吸道，腐蚀鼻中隔；溅到皮肤上，尤其是溅到粘膜，可产生软痂，并能渗入深层组织，灼伤后留有瘢痕。
This is because the concentrated sodium hydroxide solution splashed on the skin will corrode the epidermis and cause burns. It dissolves proteins and has strong irritation and corrosiveness. 0.02% solution can cause corneal epithelial damage. Oral administration of LD50 mg / kg in rabbits and intraperitoneal administration of LD50 mg / kg in mice. Dust can irritate eyes and respiratory tract, corrode nasal septum; when it splashes on skin, especially mucous membrane, it can produce soft scab and penetrate deep tissue, leaving scar after burn.