Incendiary weapons, incendiary devices, incendiary munitions, or incendiary bombs are weapons designed to start fires or destroy sensitive equipment using fire, using materials such as napalm, thermite, magnesium powder, chlorine trifluoride, or white phosphorus. Though colloquially often known as bombs, they are not explosives but in fact are designed to slow the process of chemical reactions and use ignition rather than detonation to start or maintain the reaction. Napalm, for example, is petroleum especially thickened with certain chemicals into a 'gel' to slow, but not stop, combustion, releasing energy over a longer time than an explosive device. In the case of napalm, the gel adheres to surfaces and resists suppression.
Mark 77 napalm bomb is loaded in a June 1993 training exercise onto a US Marine Strike Fighter Squadron F/A-18A Hornet aircraft
A 17th century fire or light ball from Veste Coburg, Germany
An incendiary bomb dropped on Southend-on-Sea in 1916
A German World War II 1 kg incendiary bomb
Thermite is a pyrotechnic composition of metal powder and metal oxide. When ignited by heat or chemical reaction, thermite undergoes an exothermic reduction-oxidation (redox) reaction. Most varieties are not explosive, but can create brief bursts of heat and high temperature in a small area. Its form of action is similar to that of other fuel-oxidizer mixtures, such as black powder.
A thermite mixture using iron (III) oxide
A thermite reaction using iron(III) oxide. The sparks flying outwards are globules of molten iron trailing smoke in their wake.
A thermite reaction taking place on a cast iron skillet
A thermite reaction using iron(III) oxide