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I’m an author, writing a story where a doctor from modern day gets dropped into the late 1800s in California. They need urea to help a patient.

Friedrich Wohler's synthesis of urea happened before the time of my story and the necessary chemicals, Silver Cyanate and Ammonium Chloride, appear to be part of a normal pharmacist chemicals of the time.

So my questions are:

  1. With the help of a local pharmacist, could they synthesize urea?
  2. And if so, how long would it take?

Thanks for the help.

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  • $\begingroup$ It's a fairly easy experiment to replicate, though not on an industrial scale. As a demonstration to chemistry students the whole thing can be done in a few hours. The original Wohler paper is readily available (though in German). $\endgroup$ – NotEvans. Dec 3 '17 at 15:36
  • $\begingroup$ Related: chemistry.stackexchange.com/questions/81501/… $\endgroup$ – Nilay Ghosh Dec 3 '17 at 16:11
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OK, I am not answering the question but the author Kyros might be interested in how Professor Benjamin Silliman, Sr. (1779-1864) described Wohler's synthesis in his Elements of Chemistry (1831) (Vol II, pg.600) just 3 years after the landmark experiment.

Although Silliman conceded that the properties of the "artificial" urea had the properties of urea, he appears to have been skeptical. Wohler wrote to his mentor J. J. Berzelius in Sweden about his discovery on how he, Wohler, could make urea without the need of kidney, be they animal, human or dog. Berzelius was delighted because the reaction was an example of isomerism, a term Berzelius had coined.

Preparation. — By double decomposition, by muriate of ammonia and cyanate of silver; or by single decomposition, by cyanate of lead and liquid ammonia. In this second process, the oxide of lead is liberated and a compound is obtained, in colorless rectangular prisms. In their properties, they are identical with urea, and their composition is exactly the same; they give the same results in analysis as cyanate of ammonia, provided 1 equiv. of water is supposed to exist in that salt.

Still the artificial urea, although from the mode of its formation it would appear that it contains only cyanic acid and ammonia, yields neither, by chemical agents. Potassa does not evolve ammonia, nor do the stronger acids give carbonic acid and evolve cyanic acid, with the peculiar odor which appears when the cyanates are decomposed by a stronger acid. The artificial urea gives no precipitate with salts of lead or silver.*

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    $\begingroup$ I don't know why this has been downvoted; even though there is no direct answer, this information is interesting and highly relevant. Just in case I OCRed the picture with the text to make this searchable (maybe this was the cause for a down-vote); please feel free to rollback if you think what I did was unnecessary. $\endgroup$ – andselisk Dec 11 '17 at 4:05
  • $\begingroup$ @andselisk: Are you addressiing me? $\endgroup$ – user55119 Dec 11 '17 at 14:41
  • $\begingroup$ Regarding the rollback - yes, it's up to you whether to accept it or revert; but my main intent was to improve your answer, and I just generally expressed my opinion regarding downvoting of this answer, that's all. $\endgroup$ – andselisk Dec 11 '17 at 14:48
  • $\begingroup$ Not clear about the meaning of rollback (I'm new) and what did you change. $\endgroup$ – user55119 Dec 11 '17 at 17:20
  • $\begingroup$ Oh. You need to read this: What is a 'rollback'? What I changed is in my 1st comment. It's always better to post text as, well, text, and not a picture/photo/scan to make the post searchable and maintain uniform formatting. $\endgroup$ – andselisk Dec 11 '17 at 17:34

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