important reactions, viz., the oxidation of hydrogen, carbon monoxide and
carbon, not readily accessible by conventional methods.
1
Haber then took up the question of the electrochemistry of crystalline salts,
and the most important outcome of this work was the construction and
understanding of new types of electrode such as the silver|silver chloride
electrode, involving the phase boundary potential between a solid salt and its
saturated solution. Further studies on boundary potentials led to the development of the ‘glass’ electrode and its application in determining the pH of
aqueous solutions. This was part of a general theory of the boundary potential
between an aqueous solution and a second phase permeable to water and its
ions e.g., glass, or solutions of water in organic liquids like benzene. Later, in
1909, Haber wrote of the glass electrode that it was ‘likely to prove of much
practical value’ and indeed generations of chemists have since used the glass
electrode in pH meters to accurately measure the pH of aqueous solutions.
1
Throughout his Karlsruhe period Haber was also fascinated by the
chemistry and electro-chemistry of iron. Indeed, his first paper on the subject
of electrochemistry (in 1897, just after Luggin’s arrival) dealt with electrodeposited iron plates used for the printing of banknotes.
1 But it was iron’s
passivity
33 that was to capture most of his attention and his efforts here played
an important part in the development of the subject. There was a practical
dimension of this work too in that Haber for many years investigated the
corrosion of (iron) gas and water mains due to stray currents from tramway
systems which in those days were operated by direct current. Haber looked at
the problem in Karlsruhe and Strassbourg. With characteristic thoroughness
he isolated the relevant factors; the composition and conductivity of the earth,
the direction and magnitude of small earth currents and the behaviour of iron
in the earth where chemical conditions prevented protection by passivity. He
developed a general theory, and corrosion was always found to occur where
his theory predicted it but the practical significance of his work was largely
lost with the introduction of alternating current tramway systems.
1
2.10 The Margulies Brothers
Haber reluctantly tackles the ammonia problem
This brief résumé of Haber’s early work shows that it was wide ranging and
thorough. It contributed to the understanding of a number of phenomena
but it was hardly fundamental. As an electrochemist however he was inevitably drawn to the study of chemical thermodynamics and in 1905 he
54
D. Sheppard
carbon, not readily accessible by conventional methods.
1
Haber then took up the question of the electrochemistry of crystalline salts,
and the most important outcome of this work was the construction and
understanding of new types of electrode such as the silver|silver chloride
electrode, involving the phase boundary potential between a solid salt and its
saturated solution. Further studies on boundary potentials led to the development of the ‘glass’ electrode and its application in determining the pH of
aqueous solutions. This was part of a general theory of the boundary potential
between an aqueous solution and a second phase permeable to water and its
ions e.g., glass, or solutions of water in organic liquids like benzene. Later, in
1909, Haber wrote of the glass electrode that it was ‘likely to prove of much
practical value’ and indeed generations of chemists have since used the glass
electrode in pH meters to accurately measure the pH of aqueous solutions.
1
Throughout his Karlsruhe period Haber was also fascinated by the
chemistry and electro-chemistry of iron. Indeed, his first paper on the subject
of electrochemistry (in 1897, just after Luggin’s arrival) dealt with electrodeposited iron plates used for the printing of banknotes.
1 But it was iron’s
passivity
33 that was to capture most of his attention and his efforts here played
an important part in the development of the subject. There was a practical
dimension of this work too in that Haber for many years investigated the
corrosion of (iron) gas and water mains due to stray currents from tramway
systems which in those days were operated by direct current. Haber looked at
the problem in Karlsruhe and Strassbourg. With characteristic thoroughness
he isolated the relevant factors; the composition and conductivity of the earth,
the direction and magnitude of small earth currents and the behaviour of iron
in the earth where chemical conditions prevented protection by passivity. He
developed a general theory, and corrosion was always found to occur where
his theory predicted it but the practical significance of his work was largely
lost with the introduction of alternating current tramway systems.
1
2.10 The Margulies Brothers
Haber reluctantly tackles the ammonia problem
This brief résumé of Haber’s early work shows that it was wide ranging and
thorough. It contributed to the understanding of a number of phenomena
but it was hardly fundamental. As an electrochemist however he was inevitably drawn to the study of chemical thermodynamics and in 1905 he
54
D. Sheppard