What is soda lime is as follows:
Soda lime is also called soda lime. Soda lime is white or beige powder, loose and porous, and soda lime is a mixture. So it doesn't have a specific chemical formula. It is a mixture composed of approximately 75% calcium oxide (CaO), approximately 20% water (h20), approximately 3% sodium hydroxide (NaOH), and approximately 1% potassium hydroxide (KOH). The melting point is about 318.4°C and the boiling point is about 1390°C. Part of it is easily soluble in water and reacts with water.
Soda lime, whose main components are calcium oxide, sodium hydroxide and a small amount of water, is mainly used as a desiccant and can also be used to absorb acidic gases such as carbon dioxide and sulfur dioxide. This desiccant will not work at higher temperatures if only sodium hydroxide is present.
Because sodium hydroxide can react with and corrode the most commonly used glass instruments in laboratories (containing large amounts of silica), the function of calcium oxide is to "dilute" the concentration of sodium hydroxide. A small amount of methane can be produced in the laboratory by heating it with soda lime and sodium acetate to produce sodium carbonate and methane.
Soda lime: a 1:1 mixture of sodium hydroxide and quicklime. In the chlor-alkali industry, sodium hydroxide is generally prepared in large quantities by electrolysis of concentrated brine. In the laboratory, sodium hydroxide can be prepared by reacting lime water with soda ash.
Ca(OH)2 Na2CO3=CaCO3 (precipitation) 2NaOH. Slaked lime: Calcium hydroxide Ca(OH)2. Prepared by reacting quicklime CaO with water.
CaO H2O=Ca(OH)2. Quicklime: calcium oxide. Calcined limestone (also called marble, mainly composed of calcium carbonate) at high temperature.
CaCO3=CaO CO2, hydrated lime: it is hydrated lime, two substances with the same common name.
Uses of soda lime
Soda lime is mainly used as a desiccant (calcium oxide plays a drying role). It can be used to dry neutral gases such as oxygen, and can also be used to dry alkaline gas ammonia. gas. It can also be used to absorb acidic gases such as carbon dioxide and sulfur dioxide.
If only sodium hydroxide is present, this desiccant cannot be used at higher temperatures, because sodium hydroxide can react with and corrode the most commonly used glassware in laboratories (the main component is silica) instrument. A small amount of methane can be produced in the laboratory by heating soda lime and sodium acetate to produce sodium carbonate and methane.