Lead(II) azide

Lead azide (Pb(N₃)₂) is an explosive and toxic crystalline compound.

Additional recommended knowledge

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Recognize and detect the effects of electrostatic charges on your balance

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Lead azide is highly sensitive and usually handled and stored under water in insulated rubber containers. It will explode after a fall of around 150 mm (6 in) or in the presence of a static discharge of 7 millijoules. Its detonation velocity is around 5.18 km/s (17,500 ft/s). It is used as a detonator for other, secondary, explosives. The white crystals have a density of 4.71 g/cm³. In a commercially usable form it is a white-to-buff powder.

Ammonium acetate and sodium dichromate are used to destroy small quantities of lead azide. The hygroscopicity of lead azide is very low, and water does not reduce its impact sensitivity.

Lead azide reacts with copper, zinc, cadmium, or alloys containing these metals to form other azides. For example, copper azide is even more explosive and too sensitive to be used commercially. Sodium azide is used both for the manufacture of lead azide and as preservative and diluent, which can lead to problems.

The lead salt is prepared by metathesis between sodium azide and lead nitrate or lead dissolved in nitric acid. Dextrose can be added to the solution to stabilize the product. Lead azide, when protected from humidity, is completely stable in storage.

See also: Lead styphnate