Phosphorus pentaoxide is a white crystalline chemical produced by burning elemental phosphorous. It is highly water-absorbent, making it a useful component in a variety of industrial applications. These include various chemical processes, the manufacture of optical or heat-resistant glass, and the purification of sugar. It is also frequently used as a desiccant and in the manufacture of pesticides and surfactants. Phosphorus pentaoxide should be treated with care, as it can react violently with several elements including large volumes of water.
When elemental phosphorus is burned in an oxygen-rich atmosphere, an anhydride of phosphoric acid is formed known as phosphorus pentaoxide. Also known as phosphorus pentoxide, phosphorus oxide, and phosphorus anhydride, the compound is a white crystalline powder with a penetrating odor and powerful hygroscopic properties. This means that phosphorus pentaoxide possesses a very strong affinity to water and will absorb any moisture to which it is exposed. In fact, if exposed to large volumes of water, the chemical reacts extremely violently.
This water-absorbing characteristic is put to good use in a number of industrial and food processing applications. These include the production of high quality optical and heat-resistant glass products, such as lenses and cookware. It is also commonly used in a variety of chemical processes to produce ammonium phosphate fertilizers, pesticides, and surface tension altering agents, as well as in a variety of reagent roles in chemical synthesis and polymerization.
Phosphorus pentaoxide has several other applications in the industrial sector. It is used in the food industry as a purification agent for sugar. Its water-absorbing abilities are also harnessed in the form of desiccant agents for moisture sensitive equipment. The compound is also frequently utilized in the manufacture of some medicines, printing, and dyeing agents, and a range of anti-static additives.
As mentioned previously, phosphorus pentaoxide can react very violently when exposed to excessive amounts of water. It also reacts vigorously with a number of other elements including alcohols, base metals, and sodium, as well as potassium, ammonia, and peroxides, magnesium and many oxidizing agents. It is also toxic when absorbed through the skin or inhaled, and can be fatal if swallowed. In addition, phosphorus pentaoxide is destructive to mucous membranes and can lead to permanent eye damage or serious burns where contacting the eyes or wet skin. It goes without saying that the compound's use and storage should be treated with extreme caution and all necessary safety measures should be adhered to, as well as relevant safety equipment be used at all times.