Ammonium nitrate

From Crystal growing


   Ammonium nitrate   
Names: ammonium nitrate

Formula: NH4NO3
SMILES: [NH4+].[N+](=O)([O-])[O-]
Molar mass: 80.043 g/mol
Density: 1.725 g/cm3
Crystal system: orthorhombic (α)
a=7.9804 Å, b=8.0027 Å, c=9.8099 Åα=90°, β=90°, γ=90°
orthorhombic (β)
a=4.9298 Å, b=5.7574 Å, c=5.4394 Åα=90°, β=90°, γ=90°
orthorhombic (γ)
a=7.1624 Å, b=7.7184 Å, c=5.8447 Åα=90°, β=90°, γ=90°
tetragonal (δ)
a=5.7193 Å, b=5.7193 Å, c=4.9326 Åα=90°, β=90°, γ=90°
cubic (ε)
a=4.3655 Å, b=4.3655 Å, c=4.3655 Åα=90°, β=90°, γ=90°

Color: colorless
Melting point: 169.6 °C442.75 K <br />337.28 °F <br />796.95 °R <br />
Decomposition point: -16.8 °C256.35 K <br />1.76 °F <br />461.43 °R <br /> (α)
32.3 °C305.45 K <br />90.14 °F <br />549.81 °R <br /> (β)
84.2 °C357.35 K <br />183.56 °F <br />643.23 °R <br /> (γ)
125.2 °C398.35 K <br />257.36 °F <br />717.03 °R <br /> (δ)
210 °C483.15 K <br />410 °F <br />869.67 °R <br /> (anhydrous)
Optical properties: birefringence
Magnetic properties: diamagnetic
Stability: slightly hygroscopic
Hardness: fragile
Toxicity: non-toxic


Inorganic compound, salt of ammonium ion and inorganic nitric acid. Doesn't form water hydrates.

Where to buy

In fertilizers store (as "Ammonium nitrate").


Reaction between ammonia and nitric acid

Chemical equation:

NH4OH + HNO3 = NH4NO3 + H2O

For preparation of 100.00g of ammonium nitrate а 175.13g of 25% ammonia and 121.11g of 65% acid is required.
Add acid to the flask, then add small parts of ammonium compound with stirring until it will totally dissolve . After reaction will stop, filter the solution and use it for crystal growing.

Reaction between calcium or lead(II) nitrate and ammonium hydroxide or sulfate

Chemical equation:

Ca(NO3)2 + 2NH4OH = Ca(OH)2↓ + 2NH4NO3
Pb(NO3)2 + 2NH4OH = Pb(OH)2↓ + 2NH4NO3
Ca(NO3)2 + (NH4)2SO4 = CaSO4↓ + 2NH4NO3
Pb(NO3)2 + (NH4)2SO4 = PbSO4↓ + 2NH4NO3

For preparation of 100.00g of ammonium nitrate а 82.54g of ammonium sulfate or 175.13g of 25% ammonia and 206.89g of nitrate lead(II) or 147.51g of calcium nitrate tetrahydrate is required.
Add to the flask with calcium or lead nitrate solution small parts of ammonium salt solution and stir. The large amount of poorly soluble precipitate will form. Settle it out and discard, then filter the solution carefully.

Influence of temperature

Forms a plurality of different crystal structures, depending on the solution temperature.


Dissolving is endothermic, solution cools much, so use hot water or using heat.

Storage conditions

Store in its original form or under several layers of varnish at average humidity and room temperature. Do not store in matchboxes or cotton wool and do not heat.


Temperatureгр/100,00 гр waterгр/100,00 гр ethanolгр/100,00 гр methanolгр/100,00 гр DMSOгр/100,00 гр pyridineгр/100,00 гр ammoniaгр/100,00 гр hydrazineгр/100,00 гр dimethylformamide
0°C273.15 K <br />32 °F <br />491.67 °R <br />119
10°C283.15 K <br />50 °F <br />509.67 °R <br />150
15°C288.15 K <br />59 °F <br />518.67 °R <br />~171
20°C293.15 K <br />68 °F <br />527.67 °R <br />1922.517.178
25°C298.15 K <br />77 °F <br />536.67 °R <br />212~3.137323.3539155.1
30°C303.15 K <br />86 °F <br />545.67 °R <br />242~3.75
40°C313.15 K <br />104 °F <br />563.67 °R <br />2975
50°C323.15 K <br />122 °F <br />581.67 °R <br />346~6.25
60°C333.15 K <br />140 °F <br />599.67 °R <br />4217.5
70°C343.15 K <br />158 °F <br />617.67 °R <br />499
80°C353.15 K <br />176 °F <br />635.67 °R <br />599
90°C363.15 K <br />194 °F <br />653.67 °R <br />740
100°C373.15 K <br />212 °F <br />671.67 °R <br />1024
Soluble in acetone.