Button batteries contain potassium hydroxide or sodium hydroxide. It is invaded by respiratory tract, digestive tract and skin. LD273 mg/kg via oral cavity in rats. Potassium hydroxide is a strong alkaline substance, which can dissolve protein, soften and necrosis the contact tissue, and penetrate deep within a few days. The oral LD50 of KOH solution was 365 mg/kg in rats. After oral poisoning, digestive tract pain, vomiting, diarrhea and shock may occur. Vomit contains blood and scattered epithelium. Severe cases may cause gastrointestinal perforation. After several weeks or months, esophageal stricture can occur, causing difficulty in swallowing. Acute poisoning of potassium hydroxide dust or smoke can cause chemical upper respiratory tract inflammation. Eye contact with concentrated potassium hydroxide solution can cause conjunctival edema and corneal ulcer. Oral poisoning is quickly neutralized by edible vinegar or orange juice or lemon juice, followed by egg white water, milk and vegetable oil. Prevent gastric lavage or vomiting to avoid perforation. Fasting. If suspected of upper digestive tract corrosion, esophagoscopy should be stopped within 24 hours.

　　分子式为KOH，白色晶体。饱和蒸气压(kPa)：0.13(719℃)。溶于水、乙醇，微溶于醚。易潮解并吸收二氧化碳。其化学性质相似氢氧化钠（烧碱），水溶液呈强碱性，能毁坏细胞组织。有4分子水的水合物。固体氢氧化钾遇水或水蒸气产生热量，会使易燃物质到达熄灭温度，故应置于枯燥场所储存。可使石蕊试液变蓝、酚酞试液变红。如与、硫酸、反响。如与二氧化碳、二氧化硫反响。如与铝反响。如与氧化铝反响。除此之外，氢氧化钾还能够发作其他反响，如与白磷反响生成气体。无机工业用作消费钾盐，如、亚、磷酸氢二钾等的原料。日化工业用作制造钾肥皂、洗污肥皂、洗头软皂、雪花膏、冷霜、洗发膏等的原料。工业用于制造、香兰素等原料。

　　The formula is KOH, white crystal. Saturated vapor pressure (kPa): 0.13 (719 C). Soluble in water, ethanol, slightly soluble in ether. Easy to deliquescence and absorb carbon dioxide. Its chemical properties are similar to that of sodium hydroxide (caustic soda), and its aqueous solution is strongly alkaline, which can destroy cell tissues. Hydrate with 4 molecules of water. Solid potassium hydroxide produces heat when it meets water or steam, which will make flammable substances reach extinction temperature. Therefore, it should be stored in a dry place. It can make litmus test solution blue and phenolphthalein test solution red. If with, sulfuric acid, reaction. If with carbon dioxide, sulfur dioxide reaction. For example, it reacts with aluminium. If it reacts with alumina. In addition, potassium hydroxide can produce other reactions, such as reacting with white phosphorus to produce gas. Inorganic industry is used as raw materials for consumption of potassium salts, such as potassium hydride and potassium hydrogen phosphate. The daily chemical industry is used as raw materials for making potassium soap, washing soap, shampoo soft soap, snow cream, cold cream, shampoo, etc. Industry is used for manufacturing, vanillin and other raw materials.

　　熔点为471℃，沸点925℃，于沸点开端合成，在1626℃完整合成。它微溶于乙醇，可溶于甲醇，不溶于醚；因溶解放热和溶解后溶液密度变大的缘故，在288K饱和水溶液浓度可达5.3mol/L。可以为是强碱：Kb=0.675，pK=0.17。一水合物属单斜晶系晶体，溶解度：22.3g/100g水（10℃），密度为1.51g/cm3。呈强碱性，因此其饱和溶液可使酚酞改动构造，能使酚酞由无色转变为深红色。在空气中极易吸收二氧化碳.氢氧化锂有强的腐蚀性及刺激性，应密封保管。氢氧化钠NaOH俗称火碱、烧碱、苛性钠。氢氧化钠的用处非常普遍，在化学实验中，除了用做试剂以外，由于它有很强的吸水性，可用于枯燥气体，还可用做碱性枯燥剂。

　　It was synthesized at the beginning of the boiling point and at 1626 ~C. The melting point was 471 ~C and the boiling point was 925 ~C. It is slightly soluble in ethanol, methanol and ether, and 5.3 mol/L in 288K saturated water solution due to exothermic dissolution and higher solution density after dissolution. Can be strong base: Kb = 0.675, pK = 0.17. Monohydrate is monoclinic crystal with solubility of 22.3g/100g water (10 C) and density of 1.51g/cm3. It is strongly alkaline, so its saturated solution can change the structure of phenolphthalein and change the colour of phenolphthalein from colorless to dark red. It is very easy to absorb carbon dioxide in the air. Lithium hydroxide has strong corrosiveness and irritation, and should be sealed for storage. NaOH is commonly known as caustic soda, caustic soda and caustic soda. Sodium hydroxide is widely used. In chemical experiments, besides being used as reagent, it has strong water absorption, can be used for dry gas and alkaline drying agent.