2. Shakhashui, B. 2. C h m i m l Eemonsfmtions. Vol 1; University of Wiseonin: Mad% a m . WI.1983: pp 307313. 3. Schwenek.J. R. J Ckem. Edue. 1859.36.45. 4. Skmg. D. A.;West,D. M . A u l y t i m l choAistry--~" Infrduelion, 4th ed.:Saundera:
Explosion of Nitrogen Triiodide: A Safer and Cleaner Demonstration Gordon F. Hambly and Robert Peters John Abbon College P.O. Box 2000 Ste. Anne de Bellevue, QC, H9X 3L9, Canada
The explosive decomposition of nitrogen triiodide, as described bv Shakashiri ( I ) . is a n effective demonstration, particula;ly for large clasbes, but it does have two potential drawbacks noted bv the authors and experienced on numerous occasions by us. Because a relatively large amount of iodine is used ( 2 3 g ) to prepare the explosive, the which is subsequently divided/nto tno-or three nitrogen triiodlde may not explode totally, particularly when it is still slightly damp. Secondly, cleanup can be te-
dious particnlarly when the nitrogen triiodide sample has not exploded completely. Both of these problems are circumvented by carrying out the reaction on a much-reduced scale. Students are surprised by the decibel level generated from the detonation of such a small amount of sample, and the small-scale preparation leads to rapid drying and complete destmction of the sample. Cleanup merely involves discarding what is left on the filter DaDers. S~ecificallv.0.2-0.3 e of iodine are placed in a 3 0 - k i beaker with 5 L ; of concentrated aqueous ammonia and stirred briefly. The mixture is allowed to to stand for 5 min, and the supernatant liquid is decanted from the brown solid. I t is then washed 5 times with water that is decanted off each time after allowing most of the brown solid to settle. The brown solid is then scraped onto a few pieces of filter paper and patted to absorb most of the water, then scraped onto a new filter paper. In our hands the nitrogen triiodide always has exploded totally 45 min later when touched with a long pole. The chemical equations involved in the preparation and decomposition of the nitrogen triiodide are documented thoroughly elsewhere ( I ) . Literature Cited: 1.ShaLashiri, B.S. CkemimlDemonsimfions:Uniu. Wimonah Press,1983,Vol.1, p 96.
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