biuret
Sign in to saveBiuret ( ) is a chemical compound with the chemical formula . It is a white solid that is soluble in hot water. A variety of organic derivatives are known. The term "biuret" also describes a family of organic compounds with the chemical formula , where are hydrogen, organyl or other groups. Also known as carbamylurea, it results from the condensation of two equivalents of urea. It is a common undesirable impurity in urea-based fertilizers, as biuret is toxic to plants.
Article
6 sectionsContents
- Preparation and structure
- Use as feed
- Biuret test
- History
- Related compounds
- References
Biuret ( ) is a chemical compound with the chemical formula . It is a white solid that is soluble in hot water. A variety of organic derivatives are known. The term "biuret" also describes a family of organic compounds with the chemical formula {{chem2|R^{1}R^{2}N\sC(\dO)\sN(R^{3})\sC(\dO)\sNR^{4}R^{5}|}}, where {{chem2|R^{1}, R^{2}, R^{3}, R^{4} and R^{5}|}} are hydrogen, organyl or other groups. Also known as carbamylurea, it results from the condensation of two equivalents of urea. It is a common undesirable impurity in urea-based fertilizers, as biuret is toxic to plants.
==Preparation and structure== The parent compound can be prepared by heating urea at 150 °C for ~6 hours until it gets slightly cloudy, then recrystallizing from water. After that, it can be recrystallized repeatedly from 2% sodium hydroxide solution and water to finally get base-free crystalline needles of the monohydrate which are free of cyanuric acid. While heating, a lot of ammonia is expelled: