itsbob said:
I didn't know Zinc Chloride ignited by contact with air/oxygen...
lol - it's zinc chloride once it hits the air
here ya go but the actual answer might be the last paragraph:
Hexachloroethane Smoke
HC is a pyrotechnic composition of hexachloroethane, zinc oxide, and aluminum powder. A pyrotechnic starter mixture usually ignites the burning reaction. The smoke produced is zinc chloride during burning. This zinc chloride reacts with the moisture in the air to form a zinc chloride solution in tiny droplets: smoke. When first produced, HC smoke is very hot but cools rapidly and has little tendency thereafter to rise. HC munitions generally have definite burn times, which are useful for planning purposes.
Phosphorous Smoke
Caution
HC is carcinogenic. Soldiers must wear respiratory protection (for example, a protective mask) while in HC smoke.
Phosphorus is a flammable solid that burns to form solid particles of phosphorous pentoxide in the air: smoke. The phosphorous pentoxide then reacts with moisture in the air to form phosphoric acid. We use phosphorous smokes in instantaneous-burst munitions (for example, artillery and rifle grenades), with the showers of burning phosphorous particles being highly incendiary. This makes phosphorous smoke excellent for harassing enemy personnel and starting fires, as well as its having excellent smoke properties.
Phosphorous smoke burns so hot that it tends to form a pillar of smoke, which rises rapidly. While this pillaring reduces the efficiency of phosphorous smoke, the by-product of the heat is that it obscures from the visual through the far-infrared portions of the electromagnetic spectrum. The three phosphorous smokes are WP, PWP, and RP.
Caution
Phosphorous smoke produces phosphoric acid. Soldiers must wear respiratory protection, such as protective masks, if exposed to phosphorous smoke.
WP is a spontaneously flammable natural element. It ignites on contact with air and is relatively unstable in storage. WP burns at 5,000 degrees Fahrenheit, making it the most effective smoke agent to defeat thermal imagery systems.
PWP is a formulation of white phosphorus and some other agents (for example, butyl rubber) to stabilize the smoke agent fill and slow the burning. This slowed burning tends to produce a more coherent smoke cloud with less pillaring.
RP is not spontaneously flammable, requiring ignition to burn and make smoke. RP burns at a lower temperature - 4,000 degrees Fahrenheit - which produces a more coherent smoke cloud with less pillaring. It is less incendiary than either WP or PWP, making it safer for use in smaller cartridges (for example, 40-millimeter grenades). Some munitions such as the M825 155-millimeter howitzer cartridge use felt wedges saturated with RP to produce an even distribution of smoke agent around the point of burst.
What is in the tube? What creates a 4,000 degree temp when reacting with air?
