Hydrazinium azide or hydrazine azide is a
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
with formula or . It is a
salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...
of the
hydrazinium
Hydrazinium is the cation with the formula . This cation has a methylamine-like structure (). It can be derived from hydrazine by protonation (treatment with a strong acid). Hydrazinium is a weak acid with p''K''a = 8.1.
Salts of hydrazinium ar ...
cation and the
azide anion
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...
. It can be seen as a derivative of
hydrazine and
hydrazoic acid . It is an unstable solid.
The compound is of scientific interest because of its high nitrogen content (93% nitrogen by weight) and explosive properties.
Structure
The solid undergoes structural phase transition to a different crystalline arrangement at a pressure of 13 G
Pa,
Chemistry
Hydrazinium azide decomposes explosively into hydrazine,
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous wa ...
, and
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
gas:
:12 → 3 + 16 + 19
Crystallization with an equimolar amount hydrazine yields the solid hydrazinium azide hydrazinate, ·, or , as
monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ...
crystals. This compound is less hygroscopic and less volatile than pure hydrazinium azide. It decomposes explosively into nitrogen,
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...
, and ammonia.
At pressure of 40 GPa, hydrazinium azide decomposes yielding a linear nitrogen allotrope or N≡−−N=N−−≡N, that decomposes to
ε-N2 below 25 GPa.
[
Reaction of hydrazinium azide with sulfuric acid gives quantitative yields of pure ]hydrazinediium
Hydrazinium is the cation with the formula . This cation has a methylamine-like structure (). It can be derived from hydrazine by protonation (treatment with a strong acid). Hydrazinium is a weak acid with PKa, p''K''a = 8.1.
Salt (chemistry), S ...
sulfate and hydrazoic acid:
See also
* Ammonium azide,
References
{{Reflist
Azides
Hydrazinium compounds