326 - 1836: “urila” the theory of the radicals in the study of the urine components
Autor(s): G. Dall'Olio
Issue: RIMeL - IJLaM, Vol. 2, N. 4, 2006 (MAF Servizi srl ed.)
The work of an obscure author published in 1836 on
an Italian chemistry and medicine journal is helpful in
understanding a singular attempt to explain the constitution
of urine components and, particularly, of urea,
using the theory of radicals. The author, after several
chemical experiments, hypothesizes that urine does not
contain urea but a body called “urila” that nitric acid
transforms into urea and that can be considered the
radical of urea. The hypothesis of the radical, as a group
of atoms which moves unchanged from a molecule
to another during a reaction, presented by Lavoisier in
1789 and approved by Berzelius and Liebig in 1833, is
rapidly accepted by the researchers in the first half of
‘800. Dumas and Liebig report in a paper published in
1838 that chemists discovered, investigated and characterized
the different radicals in the past and will be
engaged to the subject in the future. The chemists will
continue to investigate all the known organic substances
in order to understand “the sort of radical” to
which they are connected elucidating the characteristic
reactions and properties of each compound.