Nitrogen triiodide sensitivity

The case with which highly expl Xe03 may be formed at room temp by reaction of Xe fluorides with moisture has been strongly emphasized (Refs 2, 3 4). Xenon trioxide, Xe03, is a wh sol comparable in deton sensitivity to nitrogen triiodide and in expl force to TNT Refs 1) N. Bartlett P.R. Rao, Science 139, 506 (1963) 2) D.F. Smith, JACS 85, 816... 

Mercury azide forms a white powder, which is insoluble in cold water, but relatively soluble in hot water. When gently heated to 212 Celsius, the salt begins to fizzle. The salt detonates if rapidly heated or when heated to 300 Celsius. The precipitated mercury azide is less sensitive then lead azide, but recrystallization of this precipitated form from hot water yields the very sensitive form of mercury azide (not prepared in this procedure). This recrystallized form is too unstable for use in priming mixtures or blasting caps, and its sensitivity is related to the ammonium iodide/nitrogen triiodide salt—can be detonated by a feather. The precipitated mercury azide however, can be used as an effective substitute for LZ in blasting caps. ... 

Nitrogen triiodide (black unstable crystals) explodes at the shghtest touch when dry. When handled, it is kept wet with ether. It is too sensitive to be used as an explosive, because it cannot be stored, handled, or transported. Azides, such as lead azide and hydrazoic azide, are highly unstable. Lead azide is a severe explosion risk and should be handled under water it is also a primary detonating compound. Hydrazoic acid or hydrogen azide is a dangerous explosion risk when shocked or heated. Metal fulminates, such as mercury fulminate, explode readily when dry. They are used in the manufacture of caps and detonators for producing explosions. 

Iodine is stable under normal temperatures and pressures. Iodine may react violently with acetylene, ammonia, acetaldehyde, formaldehyde, acrylonitrile, powdered antimony, tetraamine copper(II) sulfate, and hquid chlorine. Iodine can form sensitive, explosive mixtures with potassium, sodium, and oxygen difluoride ammonium hydroxide reacts with iodine to produce nitrogen triiodide, which detonates on drying. 

The red-brown complex of nitrogen triiodide and ammonia is so sensitive to explosion that it can be detonated with a feather. Nitrogen-iodine single bonds are replaced by very stable nitrogen-nitrogen triple bonds (N2) and iodine-iodine single bonds (I2). 

The usefulness of energetic materials is in their ability to explode when desired. The energy of the stimulus that starts the explosion may range from a simple touch of a feather (nitrogen triiodide) to the impact of a shock wave (in NONEL detonators). Sensitivity of an energetic material can therefore be seen as an amount of energy that the material needs to absorb to attain a certain probability of developing an explosive reaction. 

Nitrogen triiodide is an extremely sensitive compound when dry. It explodes upon the slightest stimulus as follows ... 

Due to its extreme sensitivity, nitrogen triiodide must be stored only in wet conditions, preferably under ether [11]. It retains its sensitivity to a certain extent even under water where it can be initiated by friction [13]. 

The presence of ammonia stabilizes Nla-NHa, because ammonia retards the decomposition of Nla-NHa to pure Nla. In a concentrated ammonia solution, Nla -NHa cannot be ignited even with a very strong flash. Its stability and sensitivity are also reduced in an ammonia atmosphere. Removal of the NHa causes spontaneous explosion of nitrogen triiodide [11] and it therefore explodes immediately in high vacuum when dry [64]. Under pure water local explosions of Nla-NHa do occur, but the explosion does not spread to the surrounding material [11, 58],... 

Nitrogen triiodide has never been used in any practical industrial application due to its extreme sensitivity. Despite the inherent danger of severe injuries during its preparation and handling, it is particularly popular with young people who use it as a pyrotechnic toy that explodes by a simple touch. 

Nitrogen tri bromide, trichloride and triiodide these are all highly sensitive and violently explosive, and should never be prepared or used unless absolutely necessary. 

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