Question

Who prepared urea for the first time by heating ammonium cynate?

• A. Wohler
• B. Lavosier
• C. Fuller
• D. Van Holde

Answer 1

The correct option is A

Wohler

Urea was first prepared by Friedrich Wohler. Ammonium sulphate and potassium cynate are dissolved in equimolecular proportions in water. This reaction resulted in the formation of Ammonium Cynate which has the same chemical composition as Urea ($C{H}_4{N}_{2}O$) .When this solution was heated, it produced clear, colorless, crystalline urea which had the same characteristics as urinary urea.It turned out that ammonium cyanate and urea have the same elemental composition ($C{H}_4{N}_{2}O$) and that heating of ammonium cyanate ($N{H}_{4}OCN$) caused the atoms to rearrange resulting to its transformation into urea ($H_{2}NCON{H}_2$).