The washing method of glass instrument manufacturers to wash dirt
Washing of crystals and precipitates: For example, when sodium hydroxide or potassium hydroxide absorbs carbon dioxide in the air to form carbonate and copper hydroxide or ferric hydroxide precipitates, it can be soaked in water for several days, and then washed with dilute acid. Make it form a substance soluble in water, and then rinse with water. If there is organic precipitation, it can be washed with boiling organic solvent or sodium hydroxide solution.
Washing of residual amalgam in glass instruments: Mercury and some metals form metal alloys (amalgam), which adhere to the glass wall to form dark spots. The amalgam can be dissolved with 10% nitric acid solution by volume, and then washed with water.
Washing of dry oil, grease and paint: it can be washed with ammonia or chloroform. Unhardened grease can be washed with organic solvent; kerosene can be washed with hot soapy water; viscous oil can be washed with hot sodium hydroxide solution.
Cleaning of stains in glass beakers: white stains on glass are formed by long-term alkali storage and corrosion by alkali; yellow-brown rust spots adsorbed on glass can be washed with hydrochloric acid solution; turbidity generated during electrolysis of lead acetate, Can be washed with acetic acid; brown manganese dioxide spots can be washed with ferrous sulfate, hydrochloric acid or oxalic acid solution; ink stains on glass can be washed with soda or sodium hydroxide solution.
Washing of silver salt stains: silver chloride and silver bromide stains can be washed with sodium thiosulfate solution, and silver mirrors can be washed with hot dilute nitric acid solution to generate silver nitrate that is easily soluble in water.