Guanidine nitrate

Not to be confused with Nitroguanidine.

Guanidine nitrate is the chemical compound with the formula [C(NH₂)₃]NO₃. It is a colorless, water-soluble salt. It is produced on a large scale and finds use as precursor for nitroguanidine,^[1] fuel in pyrotechnics and gas generators. Its correct name is guanidinium nitrate, but the colloquial term guanidine nitrate is widely used.

Guanidine nitrate

Ball-and-stick models of the constituent ions
Names
IUPAC name Guanidinium nitrate
Identifiers
CAS Number	506-93-4 Y
3D model (JSmol)	Interactive image
ChemSpider	10049 Y
ECHA InfoCard	100.007.328
EC Number	208-060-1
PubChem CID	10481
RTECS number	MF4350000
UNII	B542239A4E Y
UN number	1467
CompTox Dashboard (EPA)	DTXSID3027164
InChI InChI=1S/CH5N3.HNO3/c2*2-1(3)4/h(H5,2,3,4);(H,2,3,4) Y Key: CNUNWZZSUJPAHX-UHFFFAOYSA-N Y InChI=1/CH5N3.HNO3/c2*2-1(3)4/h(H5,2,3,4);(H,2,3,4) Key: CNUNWZZSUJPAHX-UHFFFAOYAZ
SMILES C(=N)(N)N.[N+](=O)(O)[O-]
Properties
Chemical formula	CH6N4O3
Molar mass	122.1
Appearance	White solid
Density	1.436 g/cm3
Melting point	216 °C (421 °F; 489 K)
Boiling point	Decomposes commencing at 240 °C
Solubility in water	160 g/L at 20 °C
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H272, H302, H315, H318, H319, H332, H335
Precautionary statements	P210, P220, P221, P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P310, P312, P321, P330, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, P501
NFPA 704 (fire diamond)	2 1 4
Safety data sheet (SDS)	MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Production and properties

Although it is the salt formed by neutralizing guanidine with nitric acid, guanidine nitrate is produced industrially by the reaction of dicyandiamide (or calcium salt) and ammonium nitrate.^[2]

It has been used as a monopropellant in the Jetex engine for model airplanes. It is attractive because it has a high gas output and low flame temperature. It has a relatively high monopropellant specific impulse of 177 seconds (1.7 kN·s/kg).^{[note 1]}

Guanidine nitrate's explosive decomposition is given by the following equation:

[C(NH₂)₃]NO₃ (s) → 3 H₂O (g) + 2 N₂ (g) + C (s)

Uses

Guanidine nitrate is used as the gas generator in automobile airbags.^[3] It is less toxic than the mixture used in older airbags of sodium azide, potassium nitrate and silica (NaN₃, KNO₃, and SiO₂), and it is less explosive and sensitive to moisture compared to the very cheap ammonium nitrate (NH₄NO₃).^[4]

Safety

The compound is a hazardous substance, being an explosive and containing an oxidant (nitrate). It is also harmful to the eyes, skin, and respiratory tract.^[2]