White smoke emitters

A flow stream produced from boiling water appears white in color. Similar to cloud in the sky, condensed water vapor shows a white color in the atmosphere. Humid air leads to condensation when nucleating materials are present in the atmosphere, producing a white-colored fog. However, condensed water vapor and fog appear as black smoke when the background is brighter than the foreground. 

When phosphorus is burned with oxygen, phosphoms pentoxide (P4O10) is formed. P4O10 immediately absorbs humidity from the air to form phosphoric acid, 0P(0H)3, which gives rise to a white fog or smoke. A mixture of C2CI6, Zn, and ZnO reacts to produce zinc chloride (ZnCl2) according to  

Finely dispersed ZnCl2 absorbs moisture from humid air and forms a white fog. 

A mixture of ammonium perchlorate (AP NH4CIO4) and a hydrocarbon polymer (BDR) used as fuel binder forms an AP pyrolant that generates white smoke when it burns in a humid atmosphere. The polymer acts as a binder of the AP particles to form a rubber-like material. When the AP pyrolant burns, the AP particles oxidize the hydrocarbon polymer according to  

Combustion with complete gasification occurs when an AP pyrolant is composed of l2ip(0.86) and bi3I((0.14). The mass fraction of hydrogen chloride (HCl) among the combustion products is about 0.3. It is well known that HCl molecules combine with water vapor in the atmosphere to generate a white smoke. It is for this reason that AP pyrolants act as white smoke generators in a humid atmosphere. 

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