在分析化学中氢氧化钠和氢氧化钾经常可以互换du使用。
In analytical chemistry, sodium hydroxide and potassium hydroxide can often be used interchangeably with Du.
但有些应用场zhi合，两者不能换用。
However, in some application fields, the two can not be replaced.
比如氢气发dao生器，指定用氢氧化钾。
For example, hydrogen generating Dao generator is specified to use potassium hydroxide.
医用钠石灰，指定用氢氧化钠。
Sodium lime for medical use, sodium hydroxide as specified.
氢氧化钠的吸湿性要比氢氧化钾强，所以在化学分析中要常用氢氧化钾。同理要是使用它作干燥剂时就要用氢氧化钠。比如你说的医用钠石灰，指定用氢氧化钠。但是两个的价格氢氧化钠要便宜一些，可以替换时要氢氧化钠。
The hygroscopicity of sodium hydroxide is stronger than that of potassium hydroxide, so potassium hydroxide is commonly used in chemical analysis. Similarly, if it is used as a desiccant, sodium hydroxide should be used. For example, for medical sodium lime, sodium hydroxide is specified. But the price of two sodium hydroxide is cheaper, and sodium hydroxide is needed when it can be replaced.

二者都有强腐蚀性，不可与金属容器接触，且易潮解，应密封保存。
Both of them have strong corrosivity, can't contact with metal container, and are easy to deliquescence. They should be sealed and stored.
保存运输方法上二者无差别。
There is no difference in the method of preservation and transportation.
氢氧化钠的物性：
The physical properties of sodium hydroxide are as follows
纯品为无色透明晶体，相对密度2.130。熔点318.4℃。沸点1390℃。市售烧碱有固态和液态两种：纯固体烧碱呈白色，有块装、片状、棒状、粒状，质脆；纯液体烧碱为无色透明液体。固体烧碱有很强的吸湿性。易溶于水，溶解时放热，水溶液呈碱性，有滑腻感；溶于乙醇和甘油；不溶于丙酮、乙醚。腐蚀性极强，对纤维、皮肤、玻璃、陶瓷等有腐蚀作用。与金属铝和锌、非金属硼和硅等反应放出氢；与氯、溴、碘等卤素发生歧化反应；与酸类起中和作用而生成盐和水。
The purity is colorless and transparent crystal with relative density of 2.130. Melting point 318.4 ℃. Boiling point 1390 ℃. There are two kinds of caustic soda sold in the market: pure solid caustic soda is white, with block, flake, rod, granular and brittle; pure liquid caustic soda is colorless and transparent liquid. Solid caustic soda has strong hygroscopicity. It is soluble in water and exothermic when dissolved. The aqueous solution is alkaline and greasy; soluble in ethanol and glycerin; insoluble in acetone and ether. It has strong corrosivity and corrodes fibers, skin, glass, ceramics, etc. It reacts with aluminum and zinc, non-metallic boron and silicon to give out hydrogen, disproportionation with halogen such as chlorine, bromine and iodine, neutralizing with acids to form salt and water.
氢氧化钾的物性：
The physical properties of potassium hydroxide are as follows
白色斜方结晶，工业品为白色或淡灰色的块状或棒状。相对密度2.044(20℃)。熔点360.4℃。沸点1320～1324℃。易溶于水，溶解时放出大量溶解热，有极强的吸水性，在空气中能吸收水分而溶解，并吸收二氧化碳逐渐变成碳酸钾。溶于乙醇，微溶于醚。有极强的碱性和腐蚀性，其性质与烧碱相似。
White orthorhombic crystal, industrial products are white or light gray block or rod. The relative density was 2.044 (20 ℃). The melting point is 360.4 ℃. The boiling point is 1320 ～ 1324 ℃. It is easy to dissolve in water. When dissolved, it releases a large amount of heat of dissolution. It has strong water absorption. It can absorb water and dissolve in the air, and absorb carbon dioxide and gradually turn into potassium carbonate. Soluble in ethanol, slightly soluble in ether. It has strong alkalinity and corrosivity, and its properties are similar to that of caustic soda.