White phosphorus (yellow phosphorus) is an allotrope of red phosphorus, with the molecular formula P4. It is a white solid, soft and highly toxic, with a lethal dose of approximately 0.1 grams. The laboratory is stored in cold water. Light yellow or white translucent solid. Antioxidant 1010 produces blue-green phosphorescence and white smoke when exposed to dark places in the air. Fire reaches about 30°C in humid air and slightly higher in dry air. Commonly used in the preparation of chemical weapons, phosphoric acid and its compounds, pesticides, etc.
“White phosphorus bomb” is an incendiary ammunition. Because it contains a burning agent called triethyl thermite, material, so it is also called thermite incendiary bomb. This bomb can be used to burn substances that are usually difficult to ignite. It is characterized by its ability to fully burn in a small space or a space with low air density. Generally, the burning temperature can reach more than 1000 degrees Celsius, which is enough to eliminate all living organisms within an effective range. .
White phosphorus bombs are very harmful. After they hit an object, they will continue to burn until they are extinguished. If it gets on the skin, it is difficult to remove it in time. The burning temperature is high and can burn all the way to the bones. The smoke produced is extremely irritating to the eyes and nose. When you are within the range of a white phosphorus incendiary bomb, the most effective method is to immerse your whole body in water to isolate the air and reduce the temperature. Injuries should be surgically treated (removed) immediately.
People often use white phosphorus to measure the oxygen content in the air because it is flammable and the resulting product is solid. With the water-stop clamp closed, ignite the white phosphorus and tighten the rubber stopper. After the white phosphorus is fully burned and cooled to normal temperature, open the water-stop clamp. The amount of water entering the gas collecting bottle is about 1/5 of the original gas volume. In this experiment, attention should be paid to sufficient white phosphorus and good airtightness of the device.
The ignition point of white phosphorus is about 40°C, while the ignition point of red phosphorus is about 240°C for PVC resin. An experiment as shown on the right can be designed to explore the conditions for burning combustibles. It can be seen from the comparison between white phosphorus I and red phosphorus The combustion of combustibles requires its temperature to reach above the ignition point. From the comparison of white phosphorus I and white phosphorus II, it can be seen that the combustion of combustibles requires full contact with oxygen (combustion support). If an oxygen pipe is inserted into the water, when the oxygen comes into contact with the white phosphorus in the hot water, we will see that the white phosphorus in the water can also burn.
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