Red phosphorus (red phosphorus) is a simple substance of phosphorus, and it is an allotrope with white phosphorus.

Purple or brown amorphous powder, shiny. The density is 2.34 g/cm3, which sublimes when heated, but can be melted when heated to 590℃ under the pressure of 43 kPa. White phosphorus is obtained after gasification and condensation. Insoluble in water and CS2, ether, ammonia, etc. Slightly soluble in anhydrous ethanol, it is toxic and tasteless, and produces white smoke when burning, which is toxic. The chemical activity of white phosphorus is worse than that of white phosphorus, which is stable at room temperature without phosphorescence and difficult to react with oxygen. Mainly reduction, it will catch fire above 200℃ (about 260℃). It is a reducing agent when it reacts with halogen and sulfur. Used to produce safety matches, organophosphorus pesticides, phosphor bronze, etc.

1. Physical and chemical constants of substances:

GBNo。 4 100 1

Si Nuo. 7723- 14-0

Chinese name red phosphorus

English name phosphorus red

Also known as red phosphorus

Appearance and properties of molecular formula P4: purplish red amorphous powder, odorless, metallic luster, no light in the dark.

Molecular weight 123.90 Vapor pressure 4357 kPa (590℃)

Melting point is 590℃(4357kPa), insoluble in water and carbon disulfide, slightly soluble in anhydrous ethanol and soluble in alkaline solution.

Density Relative density (water =1) 2.20; The relative density (air = 1) 4.77 is relatively stable.

Danger sign 8 (flammable solids) is mainly used for making matches, pesticides and organic synthesis.

2. Impact on the environment:

This substance is harmful to the environment.

I. Health hazards

Invasion route: inhalation, ingestion and percutaneous absorption.

Health hazard: Frequent inhalation of this dust can cause chronic phosphorus poisoning. Can cause dermatitis.

Second, toxicological data and environmental behavior.

Toxicity: low toxicity.

Hazard characteristics: Danger of burning in case of open flame, high heat, friction and impact. Mixing with oxidant will form an explosive mixture. Toxic and irritating smoke is emitted when burning. The chemical reaction activity is high, which can react violently with fluorine and chlorine.

Combustion (decomposition) products: phosphorus oxide and phosphane.

3. The field emergency monitoring method:

Direct water sampling gas chromatography

4. Laboratory monitoring methods:

Gas chromatographic detection method of toxic substances in the air of working environment, edited by Chen Anzhi.

5. Environmental standards:

The maximum allowable concentration of harmful substances in the air of workplace in China (TJ36-79) is 0.03mg/m3 (yellow phosphorus).

6. Emergency treatment and disposal methods:

First, the emergency treatment of leakage

Isolate the leakage and pollution area, set warning signs around it, and cut off the fire source. It is suggested that emergency personnel wear gas masks and corresponding work clothes. Wet it with water, collect it in a dry, clean and covered container with a spark-free tool, pour it into an open place, dry it and burn it by itself. If there is a large amount of leakage, please contact the relevant technical department to determine the removal method.

Second, the protective measures

Respiratory protection: wear a dust mask.

Eye protection: Wear safety glasses if necessary.

Physical protection: wear work clothes.

Hand protection: Wear protective gloves.

Others: Smoking is strictly prohibited in the workplace. Take a shower and change clothes after work. Pay attention to personal hygiene.

Third, first aid measures.

Skin contact: Take off the contaminated clothes and rinse them thoroughly with water immediately. See a doctor.

Eye contact: lift the eyelid immediately and rinse it with running water or normal saline for at least 15 minutes.

Inhalation: leave the scene quickly and go to a place with fresh air. Give artificial respiration if necessary. See a doctor.

Ingestion: gargle, drink water, and see a doctor if you take it by mistake.

Fire extinguishing method: dry powder and sand.

white phosphorus

White phosphorus is an allotrope of phosphorus. Its molecule is a regular tetrahedron composed of four phosphorus atoms, with a bond angle of 60 and a 6 mol P bond. Its chemical formula is P4.

It is a white waxy solid, which will gradually turn into pale yellow crystals (so it is also called yellow phosphorus) when exposed to light, and it has the smell of garlic and is toxic. The ignition point is very low, it can spontaneously ignite and glow in the air.

Used to make phosphoric acid, incendiary bombs and smoke bombs.

Edit the dangers of white phosphorus in this paragraph.

White phosphorus is a kind of spontaneous combustion substance, its ignition point is 40℃, but the heat generated by friction or slow oxidation may make the local temperature reach 40℃ and burn. Therefore, it cannot be said that white phosphorus will not spontaneously ignite below 40℃.

White phosphorus is a highly toxic substance. The toxic dose of human is15mg, and the lethal dose is 50mg. After taking white phosphorus by mistake, severe gastrointestinal irritation and corrosion symptoms will soon appear. Large intake can lead to death due to systemic bleeding, hematemesis, hematochezia and circulatory system failure. If the patient survives temporarily, he may die slowly due to liver, kidney and cardiovascular dysfunction. When the skin burned by phosphorus reaches more than 7%, it can cause severe acute hemolytic anemia and die of acute renal failure. Long-term inhalation of phosphorus vapor can lead to tracheitis, pneumonia and serious bone damage.

Edit the storage of white phosphorus in this paragraph.

Because white phosphorus is very dangerous, white phosphorus dew can't be put in the air. According to the fact that white phosphorus is insoluble in water and its density is higher than that of water, a small amount of white phosphorus can be put into a wide-mouth reagent bottle filled with cold water, and enough water should be kept at all times. Covering with water can not only isolate the air, but also prevent the white phosphorus vapor from escaping, while keeping the white phosphorus below the ignition point. Unusual white phosphorus can be stored in a sealed reagent bottle and buried in sand.

Permission to edit white phosphorus in this section.

Because the ignition point of white phosphorus is low, people's hands are easily burned, so when taking white phosphorus, you must take it with tweezers and never touch it with your fingers, otherwise it will burn your hands and cause painful burns. If you need to cut a large piece of white phosphorus into small pieces, you must put it in a sink full of water and cut it under the water surface with a knife. You must never be exposed to the air, otherwise the heat generated by friction during cutting will easily make white phosphorus burn.

Edit the purpose of white phosphorus in this paragraph.

Although white phosphorus is dangerous, it also has many uses. Preparation of high purity phosphoric acid from industrial white phosphorus. White phosphorus is flammable and can produce smoke (P2O5) and fog (P2O5 and water vapor form H3PO4), which is often used to make smoke bombs in the military. White phosphorus can also be used to make red phosphorus, phosphorus trisulfide, organic phosphorus, incendiary bombs, rodenticides and so on.

White phosphorus, also known as yellow phosphorus, is a white to yellow waxy solid with a melting point of 44.65438 0℃, a boiling point of 280℃ and a density of 65438 0.82 g/cm? . White phosphorus is highly active and must be stored in water. People who inhale 0. 1 g white phosphorus will be poisoned and die. In the absence of air, white phosphorus will be converted into red phosphorus when heated to 250°C or under light. Red phosphorus is non-toxic and will not catch fire when heated above 400℃. Under high pressure, white phosphorus can be transformed into black phosphorus, which has a layered network structure and can conduct electricity. It is the most stable allotrope of phosphorus.

If oxygen is insufficient, the oxidation of white phosphorus is very slow under wet conditions, accompanied by phosphorescence. White phosphorus can be dissolved in hot concentrated alkali solution to generate phosphine and dihydrogen hypophosphite; Dry chlorine reacts with excess phosphorus to generate phosphorus trichloride, and excess chlorine reacts with phosphorus to generate phosphorus pentachloride. Phosphorus can be burned in sufficient air to produce phosphorus pentoxide, and if the air is insufficient, phosphorus trioxide is produced.

Edit the handling of articles exposed to white phosphorus in this paragraph.

Because white phosphorus is toxic and prone to spontaneous combustion, experimental articles exposed to white phosphorus must be properly handled. Knives and tweezers used should be burned with alcohol lamps in a ventilated kitchen. Paper wiped with the above tools or paper used to absorb white phosphorus cannot be thrown into the wastebasket. Then burn it in a ventilated kitchen. How many times should I wash the experimental sink?

Edit the first aid methods for people exposed to white phosphorus in this paragraph.

After people's hands come into contact with white phosphorus, they should be immediately washed with clear water, then gently wiped with 2% CuSO4 solution (or 2% AgNO3 solution), and then wet-packed with 3% ~ 5% NaHCO3 solution. It is forbidden to use oily burn ointment.

If you take white phosphorus poisoning by mistake, you should wash your stomach with copper sulfate solution as soon as possible, and the reaction is as follows:

2P+5 cuso 4+8H2O = 5Cu+2h3po 4+5h2so 4

1 1P+ 15 cuso 4+24H2O = 5Cu3P↓+6h3po 4+ 15 h2so 4

Through the above reaction, highly toxic white phosphorus is transformed into nontoxic H3PO4 or acid-insoluble Cu3P precipitate.