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.

　　分子式為KOH，白色晶體。飽和蒸氣壓(kPa)：0.13(719℃)。溶于水、乙醇，微溶于醚。易潮解并吸收二氧化碳。其化學性質相似氫氧化鈉（燒堿），水溶液呈強堿性，能毀壞細胞組織。有4分子水的水合物。固體氫氧化鉀遇水或水蒸氣產生熱量，會使易燃物質到達熄滅溫度，故應置于枯燥場所儲存。可使石蕊試液變藍、酚酞試液變紅。如與、硫酸、反響。如與二氧化碳、二氧化硫反響。如與鋁反響。如與氧化鋁反響。除此之外，氫氧化鉀還能夠發作其他反響，如與白磷反響生成氣體。無機工業用作消費鉀鹽，如、亞、磷酸氫二鉀等的原料。日化工業用作制造鉀肥皂、洗污肥皂、洗頭軟皂、雪花膏、冷霜、洗發膏等的原料。工業用于制造、香蘭素等原料。

　　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.

　　熔點為471℃，沸點925℃，于沸點開端合成，在1626℃完整合成。它微溶于乙醇，可溶于甲醇，不溶于醚；因溶解放熱和溶解后溶液密度變大的緣故，在288K飽和水溶液濃度可達5.3mol/L。可以為是強堿：Kb=0.675，pK=0.17。一水合物屬單斜晶系晶體，溶解度：22.3g/100g水（10℃），密度為1.51g/cm3。呈強堿性，因此其飽和溶液可使酚酞改動構造，能使酚酞由無色轉變為深紅色。在空氣中極易吸收二氧化碳.氫氧化鋰有強的腐蝕性及刺激性，應密封保管。氫氧化鈉NaOH俗稱火堿、燒堿、苛性鈉。氫氧化鈉的用處非常普遍，在化學實驗中，除了用做試劑以外，由于它有很強的吸水性，可用于枯燥氣體，還可用做堿性枯燥劑。

　　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.