NaOH is one of the necessary chemicals and one of the common chemicals. Pure products are colorless and transparent crystals. Density 2.130g/cm³. The melting point is 318.4 ℃. The boiling point is 1390 ° C. Industrial products contain a small amount of sodium chloride and sodium carbonate, which are white opaque crystals. There are pieces, sheets, granular and stick -like. Format 40.01 Sodium hydroxide can be used as an alkaline cleaning agent in water treatment, soluble in ethanol and glycerol, and insoluble in propylene and ether. At high temperatures, carbon sodium also has corrosion effects. A vibration reaction with halogen and other halogen such as chlorine, bromine, and iodine is generated, and salt and water are generated with acidity.

Basic information

basic introduction

Sodium hydroxide, chemical formula is NAOH, commonly known as alkali, porcholine, and harsh sodium. When dissolving, it emits ammonia flavor. It is a strong alkali with strong corrosiveness. Rehears in water) and forms an alkaline solution, and there is another moisture, which is easy to absorb water vapor (moisture) and carbon dioxide (spoiled) in the air. NaOH is one of the necessary chemicals and one of the common chemicals. Pure products are colorless and transparent crystals. Density 2.130g/cm³. The melting point is 318.4 ℃. The boiling point is 1390 ° C. Industrial products contain a small amount of sodium chloride and sodium carbonate, which are white opaque crystals. There are pieces, sheets, granular and stick -like.

Sodium hydroxide can be used as an alkaline cleaning agent in water treatment, soluble in ethanol and glycerol; insoluble in propylene, ether. At high temperatures, carbon sodium also has corrosion effects. Aversion to halogen such as chlorine, bromine, iodine. Salt and water are generated in neutralization with acids.

Physical and chemical properties

Physical properties 

Sodium hydroxide is white translucent crystalline solid. Its water solution has a astringent taste and smoothness.

Deliquescence

It is deliquescent in the air.

Water absorption

The solid alkali is very hygroscopic, exposed to the air, absorbing water molecules in the air, and finally dissolved into a solution, but sodium liquid sodium hydroxide is not hygroscopic.

Dissolved

It is easy to dissolve in water, and a lot of heat is released when dissolving. Easy to dissolve in ethanol and glycerin.

Alkaline

Sodium hydroxide is dissolved in water and will completely dissolve sodium ions and hydroxide ions, so it has the generality of alkali.

Saponification reaction

In many organic reactions, sodium hydroxide also plays a role similar to a catalyst. Among them, the most representative is the saponification reaction: RCOOR ' + Naoh = RCoona + R'Oh

Color response

The reaction can react to the indicator:

The sodium hydroxide solution is alkaline, which turns blue test solution and turns the phenolic test solution.

Corrosion

Sodium hydroxide is slightly corrosive on glass products. The two will generate sodium silicate, making the piston in the glass instrument stick to the instrument. Therefore, a glass bottle cannot be used when the sodium hydroxide solution is placed, otherwise the bottle cap may not be opened.

If the glass container is filled with hot sodium hydroxide solution for a long time, it will also cause damage to the glass container.

Folding other reactions

Bisexual metal reacts with sodium hydroxide to generate hydrogen.

The main purpose

The use of sodium hydroxide (NaOH) is extremely wide. It is used for papermaking, soap, dyes, artificial silk, aluminum, petroleum refined, cotton fabric finishing, purity of coal scor oil products, as well as food processing, wood processing and machinery industry.

Security

China Environment Standard

China's standard is the maximum allowable concentration of harmful substances in the workshop air 2mg/m

Health

Invasive ways: inhalation, eating. Sodium hydroxide is corrosive

Health hazard: This product has strong stimulation and corrosion. Dust or smoke can stimulate the eyes and the respiratory tract, corrodes the septum of the nose, and the direct contact with NaOH of the skin and the eyes will cause burns. Mistakes can cause digestive tract burns, mucosal erosion, bleeding and shock.

This product does not burn, and the water and water vapor in large amounts of heat are to form a corrosive solution; neutralize and heat up with acid occurring; it has strong corrosiveness; harm the environment.

Burning (decomposition) product: may produce harmful toxic smoke.

leakage

It isolates the pollution area and has a warning signs around it. It is recommended that emergency treatment personnel wear anti -virus masks and chemical protective clothing. Do not directly contact the leak, collect with a clean shovel in a dry and clean container, add a small amount of NaOH to a large amount of water, adjust it to neutrality, and then put it in the wastewater system. You can also rinse with a lot of water and put them into the wastewater system through diluted water washing water. If a large amount of leakage, collect and recycle or deal with harmless abolition.

Protective measures

Respiratory protection: Modify anti -virus masks if necessary.

Eye protection: wearing chemical safety protection glasses. Protective clothing: wear workwear (production of anticorrosive materials). Use it carefully, be careful to splash into clothing, mouth, nose

Hand protection: wear rubber gloves.

Others: After work, shower and dressing. Pay attention to personal cleaning.

first-aid

Skin contact: First rinse with water (dilute liquid)/dry with cloth (thick liquid), then wash and seek medical treatment with 5 ~ 10%magnesium sulfate, or 3%boric acid solution.

Eye contact: immediately lift the eyelids and rinse with a 3%boric acid solution. Medical.

Inhale: Quickly get out of the scene to fresh air. Perform artificial breathing if necessary. Medical.

Eater: Use vinegar, 3 ~ 5%acetic acid or 5%dilute hydrochloric acid, a large amount of orange juice or lemon juice when you eat a small amount; give drinking egg white, milk or vegetable oil and quickly seek medical treatment, taboo vomiting and gastric lavage.

Harm to the human body

Sodium hydroxide (NaOH) is a white crystal at normal temperature, which has strong stimulation and corrosion. Dust or smoke can stimulate the eye and respiratory tract, corrodes the nasal septum, and the direct contact with the skin and eyes and sodium hydroxide can cause burns. Mistasis can cause digestive tract burns, mucosal erosion, bleeding and shock.

Security Information

Packaging level: II

Danger category: 8

Customs Code: 2815110000

Dangerous goods transportation coding: UN18248/PG2

Wgkgermany: 1

Danger category code: R35

Safety description: S26-S45-S37/39-S24/25-S36/37/39

RTECS number: TT2975000

Dangerous product logo: C: Corrosive;