Urea

What is urea?

Urea is a solid of molecular formula H2NCONH2 with a molar mass (60.024 g/mol). It has a density under normal conditions of 0.74 g/cm3. It has a melting point (mp = 132.7 ºC). It is very soluble in water (108 g of urea dissolve in 100 ml of H2O at a temperature of 20 ºC), it is also very soluble in alcohol but insoluble in chloroform and ether. The functional group of urea is also called carbamide or carbonyldiamide.

urea XSQUKJJJFZCRTK-UHFFFAOYSA-N
3D structure

 

When urea is heated to a temperature above its melting point it decomposes forming biuret, ammonia and cyanuric acid.

H2NCONH2 NH3 + HNCO H2NCONH2H2NCONHCONH2 (biuret)

In 1828, the chemist Friedrich Wöhler synthesized this organic compound for the first time from another inorganic compound (ammonium cyanate), refuting the vitalist theory of Jacob Berzelius.

H4NOCN  H2NCONH2

Its main use is as a fertilizer and in animal feed.