Nitrogen hydracid
the nitrogen hydracid HN 3 is an unstable, colorless, the mucous membrane attractive liquid. It is extremely explosive. The azide ion N 3 - is linear built and ISO electronic with the carbon dioxide - molecule. The salts of the nitrogen hydracid are called azides. The azides are produced however, from good reason not over the nitrogen hydracid, but over the sodium azide. The nitrogen hydracid is won by the effect of the stronger sulfuric acid on the sodium azide.
| Structural formula | |||
|---|---|---|---|
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| general | |||
| name | nitrogen hydracid | ||
| other names | Azoimid, hydraulic gene azide | ||
| sum formula | HN 3 | ||
| CAS number | 7782-79-8 | ||
| short description | colorless, unstable liquid | ||
| characteristics | |||
| mol mass | 43.03 g mol | ||
| state of aggregation | liquid | ||
| density | 1.09 g/ml (25°C) | ||
| melting point | -80 °C | ||
| boiling point | 35.7 °C | ||
| steam pressure | 52300 Pa (20 °C) | ||
| solubility | for an unlimited period solubly in water | ||
| of safety references | |||
| of Gefahrensymbole | |||
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| R and S-sentences |
of R: | ||
| MAK | - | ||
| As far as possible and common, SI-UNITs are used. If not differently notes, the indicated data apply with standard conditions. | |||
Table of contents |
production and representation
- by reaction of Salpetriger acid with hydrazine in the surplus in aqueous HNO 3 or HClO 4 with [H +] > 0,2 mol/l:
- N 2 H 5 + + HNO 2 → HN 3 + H 2 O + H 3 O +
a part of the HN 3 is lost to HNO 2 over the reaction HN 3 + → N 2 + N 2 O + H 2 O.
- N 2 H 5 + + HNO 2 → HN 3 + H 2 O + H 3 O +
- By oxidation of hydrazine nitrate with aqueous HNO 3 10% with ≈40 °C with a yield of ≈35%:
- 17 N 2 H 4 + 16 HNO 3 →
- 4 HN 3 + 4 NH 4 NO 3 + 4 N 2 O + 11 N 2 + 32 H 2 O
- by electrolysis of a satisfied solution of hydrazine sulfate N 2 H 4. H 2 SO 4 [10034-93-2] in sulfuric acid 20% with 0 °C and high anodic current density.
- Metallic sodium reacts with dry ammonia with 350 °C to sodium amide NaNH 2, from which when leading up dry dinitrogen oxide N 2 O with 190°C sodium azide develops.
- Sodium azide results from reaction of sodium amide with Natriumnitrat in melted condition with 175 °C:
- 3 NaNH 2 + nano 3 → 4 NaN 3 + 3 NaOH + NH 3
production of HN 3 by effect of diluted nitric acid on hydrazine sulfate according to reaction 2.):
80 ml nitric acid [7697-37-2] HNO 3 65% is diluted with 40 ml water and to 45 g Hydraziniumsulfat [10034-93-2] H 6 N 2 O 4 S are registered. When warming up gassing begins, with the cooling hears the gassing.
The gas exists N 2 O to approximately 25 weight % of HN 3, beside nitrogen and dinitrogen oxide [10024-97-2].
Yield: ≈5 g nitrogen hydracid
characteristics
colorless one, easily mobile liquid. Highly explosive!
Density: 1,13 g/cm ³; Melting point: -80°C; Boiling point: 36°C (extrapolates)
unlimited mixable with water. Weak acid: PC s = 4,7
Water-free HN 3 explodes when warming up and during small vibration.
Solutions also concentrated may be heated up neither nor filled over plätschernd or be put on hard with the container.
Diluted ones aqueous solutions to 20% HN 3 are to be handled safe.
As container material are suitable polyethylene, glass , high-grade steel , aluminum and titanium.
use
sodium azide becomes as preservative for milk investigation samples and in the chemical synthesis for the introduction of groups of azides (- N 3) and to the representation of Triazolen uses.
A mixture from sodium azide, Kaliumperchlorat, iron (III) - oxide, filler and binder serve as propellant for Airbags.
Some salts of the nitrogen hydracid, in particular lead azide and silver azide, are useful as initial explosives.
Polyglycidylazid (GAP), (C 3 H 5 N 3 O) n [172891-14-4] is a polymer, which is used as binders high-energy in solid-propellant rockets.
connections
the salts of the nitrogen hydracid are similar in some characteristics to the chloride. Silver azide and lead azide are colorless, heavysoluble and highly explosive. Sodium azide NaN 3 [26628-22-8] is in water easily soluble (420 g/L), can be melted without decomposition and disintegrates starting from 300°C in controllable reaction in metallic sodium and nitrogen.
toxicology
nitrogen hydracid is very malicious, strong mucous membrane-provoking and has an intolerable penetrating smell. With the inhalation of small quantities first a pressure feeling in the nose develops.
Deadly dose: < 5 mg/kg; MAK: 0,1 ppm (0.27 mg/m ³), briefly 1 ppm
poisoning symptoms: Nausea, headache, swindle, blood pressure drop, heart lawn.
