Question

How was Urea produced for the first time?
(A) From ammonia
(B) From amino acids
(C) From Ammonium cyanate
(D) None of these

Answer 1

Hint: Urea was produced artificially for the first time by Friedrich Wohler. The compound he used as a reactant was an inorganic compound. Urea was finally synthesized by heating an isomer of urea.

Complete step by step answer:
Let’s know how Urea was synthesized for the first time.
- The credit to synthesize Urea artificially goes to a German chemist named Freidrich Wohler. He synthesized Urea artificially in 1828.
- He allowed Silver cyanate and ammonium chloride to react in order to synthesize urea. So, he used ammonium chloride as a source of amino group. The reaction can be given as under.

\[AgNCO + N{H_4}Cl \to \mathop {N{H_4}NCO}\limits_{{\text{Ammonium cyanate}}} + AgCl\]

So, as shown in the reaction, two compounds are obtained by the reaction of silver cyanate and ammonium chloride. They are ammonium cyanate and silver chloride.

\[\mathop {AgNCO}\limits_{{\text{Ammonium cyanate}}} \xrightarrow{\Delta }\mathop {N{H_2}CON{H_2}}\limits_{Urea} \]

Now, ammonium cyanate when heated undergoes rearrangement and without losing any atoms, it produces urea. So, we obtain Urea as a main product by the reaction of silver cyanate and ammonium chloride followed by heating of the product mixture.
- So, urea was synthesized from inorganic compounds. Urea is an organic compound. So, this was a big achievement for the scientist that they synthesized an organic compound from inorganic compounds.
So, we can conclude that Urea was synthesized from Ammonium cyanate
Therefore, the correct answer is (C).

Note: Wohler initially believed that ammonium cyanate was Urea because the molecular formula of both of them are the same which is $C{H_4}O{N_2}$. Later on, he found that after heating Ammonium cyanate, the compound obtained is urea. Note that Urea is also called Carbamide or Carbonyl Diamide.