Sodium hydroxide, also known as caustic soda, caustic soda, caustic soda, or caustic soda, is an inorganic compound with the chemical formula Na0H and a relative molecular weight of 39.9970. Sodium hydroxide has strong alkalinity and corrosiveness, and can be used as an acid neutralizer, masking agent, and precipitant.
What is sodium hydroxide
Sodium hydroxide, also known as caustic soda, caustic soda, caustic soda, or caustic soda, is an inorganic compound with the chemical formula Na0H and a relative molecular weight of 39.9970. Sodium hydroxide has strong alkalinity and strong corrosiveness. It can be used as an acid neutralizer, a masking agent, a precipitant, a precipitation masking agent, a coloring agent, a saponification agent, a peeling agent, a detergent, etc. It has a wide range of applications.
Sodium hydroxide is generally in the form of flakes or blocks, easily soluble in water (releases heat when dissolved in water) and forms an alkaline solution. It has deliquescence and is prone to absorb water vapor and carbon dioxide from the air, causing it to deteriorate. Hydrochloric acid can be added to check for deterioration.
The use of sodium hydroxide
1. Used for the production of paper and cellulose pulp; Used for the production of soap, synthetic detergents, synthetic fatty acids, and the refining of animal and vegetable fats.
2. The textile printing and dyeing industry uses it as a cotton fabric desizing agent, refining agent, and silk finishing agent.
3. The chemical industry is used to produce borax, sodium cyanide, formic acid, oxalic acid, phenol, etc. The petroleum industry is used to refine petroleum products and in drilling mud for oil fields.
4. It is also used for surface treatment in the production of alumina, metallic zinc, and metallic copper, as well as in glass, enamel, leather, pharmaceuticals, dyes, and pesticides.
5. Food grade products are used in the food industry as acid neutralizers, peelers for citrus, peach, and other fruits, detergents for empty bottles, cans, and other containers, as well as decolorizers and deodorizers.
6. Widely used basic analytical reagents. Prepare standard alkaline solution for analysis. Absorbent for small amounts of carbon dioxide and water. Neutralization of acid. Sodium salt production. Widely used in papermaking, chemical industry, printing and dyeing, medicine, metallurgy (aluminum refining), chemical fiber, electroplating, water treatment, exhaust gas treatment, etc.
7. Used as a neutralizing agent, a masking agent, a precipitant, a precipitation masking agent, and a chromogenic agent for the determination of ketosteroids by thin-layer analysis. Used for sodium salt preparation and saponification agent. Used for manufacturing various sodium salts, soaps, pulp, sorting cotton fabrics, silk, viscose fibers, recycling of rubber products, metal cleaning, electroplating, bleaching, etc.
8. In the cosmetics cream category, this product and saponification such as stearic acid act as emulsifiers, used to manufacture creams, shampoos, etc.
Properties of Sodium Hydroxide
The physical properties of sodium hydroxide include
Color and state: Sodium hydroxide is a white semi transparent solid.
Water absorption: Sodium hydroxide is easily deliquescent in the air, so it is commonly used as a desiccant, but liquid sodium hydroxide does not have water absorption.
Solubility: Very soluble in water, releases a large amount of heat when dissolved, also soluble in ethanol and glycerol, insoluble in acetone and ether.
Characteristics of aqueous solution: Its aqueous solution is strongly alkaline and can turn phenolphthalein red.
The chemical properties of sodium hydroxide include
Ionizing properties: Sodium hydroxide completely dissociates into sodium ions and hydroxide ions when dissolved in water, exhibiting alkaline properties.
Reaction in the air: Sodium hydroxide easily deteriorates into sodium carbonate in the air because the air contains acidic oxides such as dioxide
Reaction with other substances: Sodium hydroxide can react chemically with many organic and inorganic compounds, has strong corrosiveness, and can burn human skin. Sodium hydroxide is a good catalyst for many organic reactions, especially for the hydrolysis of esters. In addition, sodium oxide is one of the important raw materials for making soap and can undergo saponification reaction.
In summary, sodium hydroxide is a chemical substance with a wide range of industrial and household applications, but its high corrosiveness and danger require us to use it with caution. By understanding its basic properties and usage methods, we can better grasp its usage and precautions to ensure our safety and health.