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Smith, Watson

"The Chemistry of Hat Manufacturing Lectures Delivered Before the Hat Manufacturers' Association"

This is the first step in the
formation of aniline.
I think I have told you that if we treat zinc scraps with water and
vitriol, or water with potassium, we can rob that water of its oxygen
and set free the hydrogen. It is, however, a singular fact that if we
liberate a quantity of fresh hydrogen amongst our nitrobenzene
C_{6}H_{5}NO_{2}, that hydrogen tends to combine, or evinces an
ungovernable appetite for the O_{2} of that NO_{2} group, the tendency
being again to form water H_{2}O. This, of course, leaves the residual
C_{6}H_{5}N: group with an appetite, and only the excess of hydrogen
present to satisfy it. Accordingly hydrogen is taken up, and we get
C_{6}H_{5}NH_{2} formed, which is aniline. I told you that ammonia is
NH_{3}, and now in aniline we find an ammonia derivative, one atom of
hydrogen (H) being replaced by the group C_{6}H_{5}. I will now describe
the method of preparation of a small quantity of aniline, in order to
illustrate what I have tried to explain in theory. Benzene from coal-tar
is warmed with nitric acid in a flask.


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