NH4Cl + KCNO ----> NH4CNO + KCl ; NH4CNO(Inorganic compound) -----> NH2-CO-NH2
In above reaction Urea (an organic compound) is formed after double decomposition of NH4Cl and KCNO. IN ABOVE REACTION NH4CNO CONTAINS CARBON AND HYDROGEN AND UREA ALSO CONTAINS CARBON AND HYDROGEN BUT NH4CNO IS INORGANIC COMPOUND WHILE UREA IS ORGANIC COMPOUND. WHY?
Ammonium cyanate (NH4CNO) is an inorganic compound while urea (NH2-CO-NH2) is an organic compound although both contains C,N,H and O atoms. It is because ammonium cyanate is made up of two opposite charged polyatomic ions [NH4]+ [NCO]- so it is an ionic compound ,not a covalent compound.
When ammonium cyanate is heated then this ionic compound is changed to urea in which C,N,H and O atoms covalently bonded to form a covalent compound and organic compounds are covalent compounds ,not ionic compounds.