an inclination towards ‘chemical technology’, this machine would surely have
been an immense attraction and it possessed so many aspects of the engineering Robert was later to employ at Karlsruhe. It had a compressor that
could achieve a working pressure of almost 200 atmospheres, it circulated gas
back to the compressor—the same gas that Robert was to later encounter with
Haber. It also incorporated cooling and separation systems and customised
valves to control gas flow. It was operated too by ‘senior students’
5 and we
know that Robert was certainly one of these because of his time with
Woodland-Toms (Chap. 1). A detailed schematic of the apparatus had also
been published
10 in the prestigious Philosophical Magazine for the ‘mechanically minded’ to pore over, and Travers’ liquefier was of course in constant
use during Robert’s time at UCL (Fig. 4.1).
4.3 Beyond Engineering …
But in addition to these engineering aspects Robert had also acquired a
thorough experimental and theoretical background in reaction kinetics and
chemical equilibria culminating in the paper he produced with Donnan in
1903 viz., G. Donnan, R. Le Rossignol, ‘LXXI The velocity and mechanism
of the reaction between potassium ferricyanide and potassium iodide in
neutral aqueous solution’. J. Chem. Soc., Trans., 83, 703–716, (1903),
referred to in Chap. 1. Here, Donnan and Robert observed that when
potassium ‘ferricyanide’ and potassium iodide react in neutral aqueous
solution, potassium ferrocyanide and free iodine are gradually produced.
Conversely, a solution of iodine in potassium iodide oxidises ferrocyanide to
ferricyanide. In both cases they observed that a definite state of equilibrium
was attained expressed by the equation;
2KI þ 2K 3 FeðCNÞ 6 2K 4 FeðCNÞ 6 þ I 2
and a rough preliminary experiment, in which the amount of free iodine was
estimated by rapid titration of the cooled and diluted (‘quenched’) reaction
mixture, showed that the equilibrium could be approached from either side—
a technique employed by Ramsay in the ammonia study of 1884 and subsequently used by Haber.
This was a really complex chemical equilibrium, far more so than the
ammonia problem Robert was to tackle later in Karlsruhe. Their study
produced a substantial paper—fourteen pages in length—packed with reaction kinetic theory and the kind of experimental detail that was to later
4 The Golden Chemist
101
been an immense attraction and it possessed so many aspects of the engineering Robert was later to employ at Karlsruhe. It had a compressor that
could achieve a working pressure of almost 200 atmospheres, it circulated gas
back to the compressor—the same gas that Robert was to later encounter with
Haber. It also incorporated cooling and separation systems and customised
valves to control gas flow. It was operated too by ‘senior students’
5 and we
know that Robert was certainly one of these because of his time with
Woodland-Toms (Chap. 1). A detailed schematic of the apparatus had also
been published
10 in the prestigious Philosophical Magazine for the ‘mechanically minded’ to pore over, and Travers’ liquefier was of course in constant
use during Robert’s time at UCL (Fig. 4.1).
4.3 Beyond Engineering …
But in addition to these engineering aspects Robert had also acquired a
thorough experimental and theoretical background in reaction kinetics and
chemical equilibria culminating in the paper he produced with Donnan in
1903 viz., G. Donnan, R. Le Rossignol, ‘LXXI The velocity and mechanism
of the reaction between potassium ferricyanide and potassium iodide in
neutral aqueous solution’. J. Chem. Soc., Trans., 83, 703–716, (1903),
referred to in Chap. 1. Here, Donnan and Robert observed that when
potassium ‘ferricyanide’ and potassium iodide react in neutral aqueous
solution, potassium ferrocyanide and free iodine are gradually produced.
Conversely, a solution of iodine in potassium iodide oxidises ferrocyanide to
ferricyanide. In both cases they observed that a definite state of equilibrium
was attained expressed by the equation;
2KI þ 2K 3 FeðCNÞ 6 2K 4 FeðCNÞ 6 þ I 2
and a rough preliminary experiment, in which the amount of free iodine was
estimated by rapid titration of the cooled and diluted (‘quenched’) reaction
mixture, showed that the equilibrium could be approached from either side—
a technique employed by Ramsay in the ammonia study of 1884 and subsequently used by Haber.
This was a really complex chemical equilibrium, far more so than the
ammonia problem Robert was to tackle later in Karlsruhe. Their study
produced a substantial paper—fourteen pages in length—packed with reaction kinetic theory and the kind of experimental detail that was to later
4 The Golden Chemist
101