Phosphorus
Phosphorus is an example of a material that is too reactive to be of any general use as a pyrotechnic fuel, although it is increasingly being employed in military white smoke compositions, and it has traditionally been used in toy pistol caps and trick noisemakers ("party poppers").
Phosphorus is available in two forms, white (or yellow) and red. White phosphorus appears to be molecular, with a formula of P,,. It is a waxy solid with a melting point of 440C, and ignites spontaneously on exposure to air. It must be kept cool and is usually stored under water. It is highly toxic in both the solid and vapor form and causes burns on contact with the skin. Its use in pyrotechnics is limited to incendiary and white smoke compositions. The white smoke consists of the combustion product, primarily phosphoric acid (H 3PO,,).
Red phosphorus is somewhat more stable, and is a reddishbrown powder with a melting point of approximately 590°C (in the absence of air). In the presence of air, red phosphorus ignites near 260°C. Red phosphorus is insoluble in water. It is easily ignited by spark or friction, and is quite hazardous any time it is mixed with oxidizers or flammable materials. Its fumes are highly toxic. Red phosphorus is mixed as a water slurry with potassium
Red phosphorus is mixed as a water slurry with potassium chlorate for use in toy caps and noisemakers. These mixtures are quite sensitive to friction, impact, and heat, and a large amount of such mixtures must never be allowed to dry out in bulk form.