Urea

Urea ;
Names:	urea; carbamide; carbonylamide; diaminomethanal;
Formula:	CO(NH4)2;
Molar mass:	64.088 g/mol;
Density:	1.32 g/cm3;
Crystal system:	tetragonal; a=5.661 Å, b=5.661 Åα=90°, β=90°, γ=90°;
Shapes:	https://en.crystalls.info/w/uploads/media/5/52/Needle.json Needle ;
Color:	colorless;
Melting point:	132.7 °C405.85 K <br />270.86 °F <br />730.53 °R <br />;
Decomposition point:	174 °C447.15 K <br />345.2 °F <br />804.87 °R <br />;
Refractive index:	1.4840 ;
Magnetic properties:	diamagnetic; χ=-3.34 · 10-5cm³/mol;
Stability:	stable;
Hardness:	fragile;
Toxicity:	non-toxic; LD50=12000mg/kg

Description

Organic compound, carbonic acid diamide. Doesn't form water hydrates.

Where to buy

Can be bought in fertilizers store (as "Urea").

Influence of impurities

In water solutions may form adducts with other compounds. Adduct crystals have different shapes and don't dehydrate as much.

Notes

In most cases, poly crystals are formed

Solubility

TableGraph

Temperature	g/`100,00` g water	g/`100,00` g ethanol	g/`100,00` g methanol	g/`100,00` g diethyl ether	g/`100,00` g pyridine	g/`100,00` g pyridine 50%	g/`100,00` g ethyl acetate	g/`100,00` g ethylene glycol	g/`100,00` g propanol	g/`100,00` g isopropanol	g/`100,00` g isobutanol	g/`100,00` g ammonia	g/`100,00` g acrylic acid 70%	g/`100,00` g allyl alcohol	g/`100,00` g isoamyl alcohol
-26.5°C246.65 K <br />-15.7 °F <br />443.97 °R <br />												`25.1`
-18.1°C255.05 K <br />-0.58 °F <br />459.09 °R <br />			`3.48`
0°C273.15 K <br />32 °F <br />491.67 °R <br />	`67`	`2.6`	`15`						`1.65`
5.8°C278.95 K <br />42.44 °F <br />502.11 °R <br />												`63.52`
10°C283.15 K <br />50 °F <br />509.67 °R <br />	`84`	`4`							`2`						`0.7`
15°C288.15 K <br />59 °F <br />518.67 °R <br />
19.5°C292.65 K <br />67.1 °F <br />526.77 °R <br />														`9.37`
20°C293.15 K <br />68 °F <br />527.67 °R <br />	`104.7`	`6.73`	`22`	`0.00056`		`21.53`			`2.56`	`2.6`	`6.2`				`1.2`
24°C297.15 K <br />75.2 °F <br />534.87 °R <br />												`107.6`
25°C298.15 K <br />77 °F <br />536.67 °R <br />		`6.2`			`0.96`		`0.08`	`44`
30°C303.15 K <br />86 °F <br />545.67 °R <br />	`136`	`7.2`							`3.6`						`1.6`
35°C308.15 K <br />95 °F <br />554.67 °R <br />													`97.043`
40°C313.15 K <br />104 °F <br />563.67 °R <br />	`165.4`	`9.16`							`4.8`						`2.1`
50°C323.15 K <br />122 °F <br />581.67 °R <br />	`205`	`11.7`							`6.2`				`119.7`
60°C333.15 K <br />140 °F <br />599.67 °R <br />	`246`	`15.1`	`62.8`						`7.7`
70°C343.15 K <br />158 °F <br />617.67 °R <br />	`314.6`	`20.2`							`9.8`				`172.32`
80°C353.15 K <br />176 °F <br />635.67 °R <br />	`400`								`12.3`
90°C363.15 K <br />194 °F <br />653.67 °R <br />	`525`								`17`						`5.5`
98°C371.15 K <br />208.4 °F <br />668.07 °R <br />									`18.06`
100°C373.15 K <br />212 °F <br />671.67 °R <br />	`733`

Highly soluble in hydrogen fluoride. Soluble in sulfur dioxide. Slightly soluble in benzene. Insoluble in chloroform.

Gallery

UreaTwitterDejan VinkovicTwitter
Monocrystals grown from solution containing small amount of sulfuric acidUrea, Egor Kazakov, VKontakteEgor KazakovVKontakte
UreaMagicDave131, redditMagicDave131Reddit
UreaMaxim MartinovMaxim Martinov
UreaMaxim Skokov, VKontakteMaxim SkokovVKontakte

Video

Sources

Amides
Paracetamol (C₈H₉NO₂) • Thiourea (CS(NH₄)₂) • Urea (CO(NH₄)₂)

Urea compounds
Hexakarbamatzinc sulfate ([(CON₂H₄)₆Zn]SO₄) • Nitratopentakis-karbamatbismuth(III) nitrate ([Bi(NO₃)(CO(NH₂)₂)₅](NO₃)₂) • Urea ((NH₂)₂CO) • Urea and sodium chloride complex (CO(NH₄)₂ · NaCl) • Urea citrate ((NH₂)₂CO · C₆H₈O₇)

Urea
Names:	urea carbamide carbonylamide diaminomethanal
Formula:	CO(NH₄)₂
Molar mass:	64.088 g/mol
Density:	1.32 g/cm³
Crystal system:	tetragonal a=5.661 Å, b=5.661 Åα=90°, β=90°, γ=90°
Shapes:	Needle
Color:	colorless
Melting point:	132.7 °C405.85 K <br />270.86 °F <br />730.53 °R <br />
Decomposition point:	174 °C447.15 K <br />345.2 °F <br />804.87 °R <br />
Refractive index:	1.4840
Magnetic properties:	diamagnetic χ=-3.34 · 10^-5cm³/mol
Stability:	stable
Hardness:	fragile
Toxicity:	non-toxic LD₅₀=12000mg/kg