PMDC Verified Question 14 of 83
Urea was first synthesized by Wohler from an inorganic material named
A
Ammonium bicarbonate
B
Ammonium oxalte
C
Ammonium nitrate
D
Ammonium cyanate
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: Ammonium cyanate
Concept:

The synthesis of urea in 1828 by Friedrich Wöhler marked a turning point in chemistry, disproving the Vital Force Theory by showing organic molecules could be made from inorganic salts.

Solution:

  • Wöhler heated an aqueous solution of the inorganic salt ammonium cyanate (\( \text{NH}_4\text{CNO} \)).


  • Upon heating, the molecules underwent an internal rearrangement to form urea (\( \text{CO(NH}_2)_2 \)), an organic compound.


Why other options are incorrect:

The other ammonium salts (bicarbonate, oxalate, nitrate) do not possess the necessary carbon-nitrogen-oxygen stoichiometry to spontaneously rearrange into urea upon heating.

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