Christian Friedrich Schönbein
Encyclopedia
Christian Friedrich Schönbein (18 October 1799 – 29 August 1868) was a German-Swiss chemist
who is best known for inventing the fuel cell
(1838) and his discoveries of guncotton and ozone
.
, Swabia. Around the age of 13 he was apprenticed to a chemical and pharmaceutical firm at Böblingen
. Through his own efforts, he acquired sufficient scientific skills and knowledge to ask for, and receive, an examination by the professor of chemistry at Tübingen
. Schönbein passed the exam and, after a series of moves and university studies, eventually acquired a position at the University of Basel
in 1828, becoming a full professor in 1835. He remained there until his death in 1868, and was buried in Basel.
of water
at the University of Basel that Schönbein first began to notice a distinctive odor in his laboratory. This smell gave Schönbein the clue to the presence of a new product from his experiments. Because of the pronounced smell, Schönbein coined the term ‘ozone’ for the new gas, from the Greek word ‘ozein’, meaning ‘to smell’. Schönbein described his discoveries in publications in 1840. He later found that the smell of ozone was similar to that produced by the slow oxidation of white phosphorus
.
The ozone smell Schönbein detected is the same as that occurring in the vicinity of a thunderstorm, an odor that indicates the presence of ozone in the atmosphere.
and sulfuric acid
. After using his wife's cotton
apron to mop it up, he hung the apron over the stove to dry, only to find that the cloth spontaneously ignited and burned so quickly that it seemed to disappear. Schönbein, in fact, had converted the cellulose
of the apron, with the nitro groups (added from the nitric acid) serving as an internal source of oxygen
; when heated, the cellulose was completely and suddenly oxidized.
Schönbein recognized the possibilities of the new compound. Ordinary black gunpowder
, which had reigned supreme in the battlefield for the past 500 years, exploded into thick smoke, blackening the gunners, fouling cannons and small arms, and obscuring the battlefield. Nitrocellulose was perceived as a possible "smokeless powder" and a propellant for artillery
shell
s thus it received the name of guncotton.
Attempts to manufacture guncotton for military use failed at first because the factories were prone to explode and, above all else, the burning speed of straight guncotton was always too high. It was not until 1884 that Paul Vieille tamed guncotton into a successful progressive smokeless gunpowder called Poudre B
. Later on, in 1891, James Dewar
and Frederick Augustus Abel
also managed to transform gelatinized guncotton into a safe mixture, called cordite
because it could be extruded into long thin cords before being dried.
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...
who is best known for inventing the fuel cell
Fuel cell
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...
(1838) and his discoveries of guncotton and ozone
Ozone
Ozone , or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope...
.
Life
Schönbein was born at MetzingenMetzingen
Metzingen is a Swabian city with about 22,000 inhabitants, in the state of Baden-Württemberg in the southwest of Germany, south of Stuttgart.-History:The city is mentioned for the first time in documents from 1075...
, Swabia. Around the age of 13 he was apprenticed to a chemical and pharmaceutical firm at Böblingen
Böblingen
Böblingen is a town in Baden-Württemberg, Germany, seat of Böblingen District. Physically Sindelfingen and Böblingen are continuous.-History:Böblingen was founded by Count Wilhelm von Tübingen-Böblingen in 1253. Württemberg acquired the town in 1357, and on 12 May 1525 one of the bloodiest battles...
. Through his own efforts, he acquired sufficient scientific skills and knowledge to ask for, and receive, an examination by the professor of chemistry at Tübingen
Tübingen
Tübingen is a traditional university town in central Baden-Württemberg, Germany. It is situated south of the state capital, Stuttgart, on a ridge between the Neckar and Ammer rivers.-Geography:...
. Schönbein passed the exam and, after a series of moves and university studies, eventually acquired a position at the University of Basel
University of Basel
The University of Basel is located in Basel, Switzerland, and is considered to be one of leading universities in the country...
in 1828, becoming a full professor in 1835. He remained there until his death in 1868, and was buried in Basel.
Ozone
It was while doing experiments on the electrolysisElectrolysis
In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...
of water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
at the University of Basel that Schönbein first began to notice a distinctive odor in his laboratory. This smell gave Schönbein the clue to the presence of a new product from his experiments. Because of the pronounced smell, Schönbein coined the term ‘ozone’ for the new gas, from the Greek word ‘ozein’, meaning ‘to smell’. Schönbein described his discoveries in publications in 1840. He later found that the smell of ozone was similar to that produced by the slow oxidation of white phosphorus
Phosphorus
Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...
.
The ozone smell Schönbein detected is the same as that occurring in the vicinity of a thunderstorm, an odor that indicates the presence of ozone in the atmosphere.
Explosives
Although his wife had forbidden him to do so, Schönbein occasionally experimented at home in the kitchen. One day in 1845, when his wife was away, he spilled a mixture of nitric acidNitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
and sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
. After using his wife's cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
apron to mop it up, he hung the apron over the stove to dry, only to find that the cloth spontaneously ignited and burned so quickly that it seemed to disappear. Schönbein, in fact, had converted the cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....
of the apron, with the nitro groups (added from the nitric acid) serving as an internal source of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
; when heated, the cellulose was completely and suddenly oxidized.
Schönbein recognized the possibilities of the new compound. Ordinary black gunpowder
Gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...
, which had reigned supreme in the battlefield for the past 500 years, exploded into thick smoke, blackening the gunners, fouling cannons and small arms, and obscuring the battlefield. Nitrocellulose was perceived as a possible "smokeless powder" and a propellant for artillery
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
shell
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...
s thus it received the name of guncotton.
Attempts to manufacture guncotton for military use failed at first because the factories were prone to explode and, above all else, the burning speed of straight guncotton was always too high. It was not until 1884 that Paul Vieille tamed guncotton into a successful progressive smokeless gunpowder called Poudre B
Poudre B
Poudre B : was the first practical smokeless gunpowder. Originally called "Poudre V" from the name of the inventor, Paul Vieille, it was later renamed "Poudre B" to distract German espionage...
. Later on, in 1891, James Dewar
James Dewar
Sir James Dewar FRS was a Scottish chemist and physicist. He is probably best-known today for his invention of the Dewar flask, which he used in conjunction with extensive research into the liquefaction of gases...
and Frederick Augustus Abel
Frederick Augustus Abel
-External links:...
also managed to transform gelatinized guncotton into a safe mixture, called cordite
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance...
because it could be extruded into long thin cords before being dried.
Selected writings
- The Letters of Faraday and Schoenbein 1836-1862 London: Williams & Norgate 1899.
- The Letters of Jöns Jakob Berrelius and Christian Friedrich Schönbein, 1830-1847 London: Williams & Norgate 1900.
Further reading
- Brown G. I. The Big Bang: A History of Explosives, Sutton Publishing; 1998 (ISBN 0750937920)