History of chemistry

from Wikipedia, the free encyclopedia

The history of chemistry has been closely linked to the history of manual activities that are aimed at the extraction and transformation of materials since the earliest times. In addition to the practical aspects, chemistry has endeavored since its inception, together with its sister science , physics , to explain the inner nature of matter .

At the beginning of the modern era , ancient chemical practice was combined with medieval alchemy, which was conveyed to Europe by scholars who wrote in Arabic . From the end of the 18th century chemistry developed into an exact natural science , which then began in the 19th century to provide an enormous wealth of practical results that led to the establishment of a chemical industry .

The industrial application of chemistry also caused ever greater environmental damage , which led to the emergence of an environmental movement from around 1970 that seeks to induce the chemical industry and society as a whole to act sustainably without environmental pollution .

Chemistry is a differentiated science that has a wide variety of research goals in its numerous branches and uses a variety of technologies for the conversion of substances of all kinds in chemical reactions .

The roots of chemistry

antiquity

Around 1000 BC In many areas of the Near East, Egypt and Greece, metal extraction from ores was known. Found use gold , silver , iron (500 v. Chr. In Europe, 4000 v. Chr. In Egypt), copper (4000 v. Chr.), Tin (alloy with copper 3000 v. Chr.), Lead (500 v Used for water pipes, writing boards, coins, cooking vessels in Rome), mercury (300 BC, Theophrast and Dioscorides, liquid silver , obtained from cinnabar using copper and vinegar), as well as substances such as sulfur , saltpeter or coal. The metal names were associated with days of the week and planets. The methods of making clay (for pottery ), earthenware , glass (1500 BC, Egypt, blown glass, Rome 30 BC) and porcelain (China) were also known.

Furthermore, were ointments , soaps , oils, milk and cheese, wine , the beer brewing , vinegar , the papyri, leather production and the coloring (dyes: henna , indigo , madder , saffron, pigments (eg. Red lead , white lead , cinnabar , Ocher , bluestone, verdigris , galena , arsenic sulphide and antimony sulphide), essential oils, salts ( alum , table salt ) (from evaporation of sea water, to preserve food). Sulfur vapors ( sulfur dioxide , sulphites in water ) were used for smoking and cleaning of substances, for the preservation of wine, for the destruction of dyes, for the production of alum. The Egyptians, Greeks and Romans were already familiar with various medicines such as vitriol ( copper sulfate , emetic), alum (for gargling), iron rust, litharge , poppy seed extract , Henbane , mandragora root, hyoscyamine , scopolamine (for intoxicating, numbing).

Chemistry in antiquity differed from today's manufacturing processes in technical chemistry mainly in that these processes were not very complicated and could therefore be practiced in many cultures.

The extraction of metals was of great importance in earlier times. From metals - according to the specifications of the human mind - forms for tools, devices of daily use, coins, armor could be created first in thought, then materially, which then had a considerable influence on social life. The idea - according to Plato, the world soul - is transformed by the metal production into objects that the invention and the tool can survive beyond the death of the inventor. Even the Greeks transferred the state of the community to metals ( Iron Age , Silver Age, Golden Age ) and coin metal (gold, silver, iron) could enable members of society to be more equitable (coin metal: iron in Sparta) or to provide special and high achievements Sanction earnings with valuable coins (coin metals: gold, silver).

Many Greeks believed in a single primordial substance in the world. Thales of Miletus (original substance: water), Anaximenes of Milet (original substance: air), Heraklit (original substance: fire). Empedocles of Agrigento saw the four primary substances united: earth, water, air and fire. He thought of a fuel in the air (basis of the later phlogiston theory according to Stahl) and assumed that the four primary substances mix randomly, whereby love and quarrel between the primary substances play a role. All things in the world arise from the mixture of these four elements. Empedocles also suspected that air is made of matter and that there can be no vacuum, since he had investigated the principle of a pipette . Democritus of Abdera ( Democritus ) and Leucippus believed in indivisible minute particles of a substance they called atom .

Even Plato and Aristotle dealt with natural philosophy . Aristotle believed in the four original elements of Empedocles, but he also believed in four original properties (warm-cold, dry-moist). Each element has two original properties (e.g. water: damp, cold). Substances should be able to transform by exchanging properties. Another primal element was added by Aristotle - the ether. This substance should permeate everything forever and unchangeably, be contained in all substances. Aristotle also recognized that there is a relationship between metals in smelting, it depends on the correct mixing ratio. He transferred these thoughts to the body fluids of sick people (see humoral pathology ). The sick person could possibly recover by means of vegetable juices or salts, this was the basis for later medicinal experiments ( Galenos ) and for later medicines. Aristotle saw all earthly processes as a reflection of the heavenly processes. The types of metal were later assigned to individual planets.

Alchemy later developed from natural philosophy . In the early days, alchemy combined magic and mysticism with the process of metal conversion, chemical-physical cleaning processes and the production of colorants.

In the age of Hellenism , due to the expansion of the markets, methods grew in importance by which cheap imitations of expensive natural materials and other goods (precious stones, purple and other dyes, etc.) could be produced: synthetic "gold", colored glass, imitation pearls, etc.

In Egypt, religion , astrology and magic were mixed together in the 2nd century AD . In the religious direction of Gnosis , which had a different orientation than later Christianity towards the evil in the world ( theodicy ), inner enlightenment through alchemy played an important role. In the creation history of the Gnostics , chemical terms such as sublimation and distillation (spiritualization) or mixtures ( purification ) were used. The first detailed drawings and descriptions of many chemical processes in Egypt around AD 400 come from Zosimus from Panopolis . Older sources (e.g. from Bolos von Mendes 250–200 BC) are also known. Instead of the four primordial elements, two basic substances of matter were conceived in this phase. Mercury and sulfur . The first-mentioned substance is a liquid metal that solidifies when it acts on other metals (amalgamation). The second substance burns easily with the formation of flames, producing gases. Furthermore, mercury and arsenic were regarded as the male principle, and sulfur as the female principle.

middle Ages

With the spread of Islam , ancient Greek knowledge passed to Islamic scholars. An important Islamic alchemist was, for example, Jabir ibn Hayyān .

The theories of the alchemists in chemistry in the Middle Ages arose not only from their experimental experiences, but also from the teachings of astrology and an understanding of the world that today would be called esoteric , but which was actually an early attempt at a phenomenological theory within the framework of the axiomatics of the time .

Albertus Magnus ; Fresco (1352), Treviso, Italy

From the 12th century - thanks to contacts with the Arab alchemists - the “alchemy boom” broke out over Europe: In 1085 Gerhard von Cremona wrote Europe's first chemistry book in Toledo : “ The book of alums and salts ”, Albertus Magnus researched from 1193–1280 in Cologne, and even the church scholar Thomas Aquinas operated "studiae alchymicae" with recourse to Aristotle and the Bible.

The aim of alchemy was to turn base metals into gold by means of transmutation and to find the philosopher's stone in the Great Work on your own purification . However, alchemy was integrated into the knowledge of nature with magical, holistic endeavors to bring the substances and the soul of the experimenter into a purified state.

Roger Bacon

Roger Bacon (1210–1292) introduced the experiment as the most important working method of the alchemists (“Sine experientia nihil sufficienter sciri potest”: nothing can be sufficiently known without an experiment) - the scales, however, remained a device for measuring the starting substances. It was not until Lavoisier - from 1775 - that it became a means of measuring research.

Albertus Magnus was nevertheless an important alchemist and chemist of the Middle Ages, who, as a Dominican , kept his theories within the limits set by the church. He was the first to isolate the element arsenic .

The Alchemist is looking for the Philosopher's Stone by Joseph Wright of Derby , illustrating the discovery of phosphorus by Hennig Brand

The alchemist of the Middle Ages was mostly a clergyman with a certain education, it was not until the end of the Middle Ages that alchemy appeared in broader layers. It was generally accepted and promoted or even practiced by high princes and clergy. Important alchemists were e.g. B. Vannoccio Biringuccio , Paracelsus , Libavius , Basilius Valentinus , Johann Rudolph Glauber . Criticism was directed against excesses and frauds, so were decrees like the bull of Pope John XXII. of 1317 not directed against alchemy, but against fraudulent alchemists, in the case of the bull against coin forgers. The belief in the possibility of gold production through alchemy or the possibility of a life-extending elixir was widespread in all classes. Martin Luther did blaspheme against the alchemists and the alchemist Süple at table speeches , but because of the spiritual background with regard to allegories, transmutations and the resurrection of the dead on the last day he found the actual art in laudable agreement with Christianity.

Since the 11th century, alcohol has been produced on a large scale by distilling wine. In the 13th century, sulfuric acid (or vitriolic acid, royal acid ) and nitric acid (or septic acid ) were extracted. For these sectors of the economy people were also needed who could extract the substances. In the 14th century, the need for gunpowder , a mixture of sulfur, saltpeter and charcoal, for the emerging firearms increased . Especially the gunpowder production in powder mills required a certain basic knowledge of the chemicals and working techniques to be used in order to enable safe working. From 1420 the first paper mills were built on the Rhine; The need for paper soon increased with the invention of the printing press by Gutenberg. In the Holy Roman Empire of the German Nation around 1520, around 100,000 people were employed in the mining and steel industry. Important books were now also published on mining and metallurgy (e.g. by Georgius Agricola , Bermanus sive de re metallica (1530), De Re Metallica, libri XII (1546)). Alchemy has been discredited since the 14th century, the philosopher's stone was not found and gold-making was also unsuccessful. Papal prohibitions on alchemy and the threat of excommunication followed.

From the 16th to the 18th century, the princes sometimes employed alchemists. Despite the small number of alchemists, there were also important discoveries. In 1669, Hennig Brand , a German pharmacist and alchemist, discovered the chemical element phosphorus while searching for the philosopher's stone when distilling urine and glowing the residue . The alchemist and chemist Johann Friedrich Böttger , together with Ehrenfried Walther von Tschirnhaus, even found the European counterpart of Chinese porcelain in 1708 , but the “Philosopher's Stone” remained a fantasy .

The beginnings of a systematic practical chemistry

The social changes in the age of the Renaissance: the invention of the printing press by Gutenberg (1450), the discovery of America (1492), the Reformation by Martin Luther also brought innovations to alchemy. Important alchemists of this time were Paracelsus (1493–1541), Faust (1480–1540), Vanoccio Biringucci (1480–1539), Georgius Agricola (1494–1555). The books of the alchemists broadened the exact knowledge in the alchemistic application.

metallurgy

As early as 1500 there were first writings on metal extraction in Germany.

Vannoccio Biringuccio wrote the Pirotechnica work in 1540 and thus gave a comprehensive overview of metal science, weapon production and machines.

Georgius Agricola

In the 16th century, the Saxon scholar Georgius Agricola wrote his twelve-volume work on metallurgy , De re metallica libri XII (Basel 1556), volume seven of which was for a long time a standard work for early analytical chemistry , i.e. for detection reactions and the testing of metals , has been. Some sections of his work were based on the work Pirotechnica by Vannoccio Biringuccio. For the first time, metals such as bismuth and zinc were described in the work. However, other names were used for these metals ( Kobelt or Cadmia metallica ); It was not until 1617 that the word zinc was used in Löhneyss work ( Das Buch vom Bergwerk ) . De re metallica represents the first comprehensive and systematic compilation of the metallurgical knowledge of the early modern period. It also contains a summary of the knowledge of the time from the art of tasting for the analysis of metal ores and alloys.

Drug manufacturing

In addition to metallurgy, pharmacy was of particular importance in practical chemistry in the 16th century . The Swiss-Austrian doctor and natural scientist Paracelsus founded chemical research to fight diseases ( iatrochemistry ). He tried to interpret the processes of life chemically and to put chemistry at the service of medicine. He is convinced that diseases come from outside and can therefore be treated with chemicals from outside.

Paracelsus also described symptoms of poisoning through harmful substances (lead salts) and is therefore considered to be a co-founder of toxicology. He also introduced the word alcohol for the first time and suggested the need to isolate medicinal ingredients from plants ( quintia essentia ).

However, Paracelsus also used toxic substances to fight diseases, hoping that the right dose of a substance would be crucial for recovery. His medicine was fought against by many critics, however, the antimony preparations from Paracelsus were banned in France by a parliamentary decision in 1566. However, many later alchemists were followers of the teachings of Paracelsus, such as Johann Baptista van Helmont , Andreas Libavius , Johannes Hartmann . The latter was given a chair for iatrochemistry in Marburg for the first time in 1609.

In the course of time, many devices and processes have been developed, especially in the field of pharmaceutical production, some of which are still used in chemical laboratories today : mortars for comminuting, glass flasks, retorts , spatulas, precise scales , stills, etc.

The Beginning of Measurement Research and Early Theories

From Glauber to Lavoisier

Antoine Laurent de Lavoisier

The time of the Renaissance produced chemists who did not rely on blind faith in old authorities, but developed their own ideas. The development of bookkeeping in Italy led to increased trade and accessibility of goods and raw materials, which also improved opportunities for chemists. Johann Rudolph Glauber was the first chemist in Germany who was independent of princely donations and was able to combine research and a small independent chemical production .

Earlier scientists, including alchemists, were scholars whose foundations lay in ancient languages ​​and religion. Only cautiously - and sometimes also in fear of theological consequences - did new theories and new insights prevail in science. The number of scholars paid by princes was still very small in Europe between the 17th and 18th centuries. In England some wealthy noblemen took an interest in chemistry.

The English nobleman Robert Boyle , who investigated the diversity of substances and their transformation into other substances, criticized the concept of elements in alchemy in his influential work "The Skeptical Chymist" in 1661 and prepared the modern concept: a chemical element is an im Experiment material that cannot be further decomposed. Boyle realized that breathing and heating metals with fire consumed some of the air and made the metal heavier. Boyle also founded the first scientific society, the Royal Society .

Georg Ernst Stahl established the phlogiston theory (1697) to describe the processes involved in combustion, fermentation, putrefaction, oxidation and reduction. Many important chemists between 1700 and 1787 believed in the phlogiston theory: Joseph Black , Henry Cavendish , Joseph Priestley , Carl Wilhelm Scheele , Andreas Sigismund Marggraf , Lorenz Friedrich von Crell , Anders Jahan Retzius . This theory was held on for almost a hundred years until Antoine Laurent de Lavoisier and others clarified oxidation . By replacing the phlogiston theory with the oxidation theory, the bridge to theology, the belief about body, soul and fire, was shaken.

The phlogiston theory had to be abandoned when Antoine Laurent de Lavoisier , assisted in the experiments by his wife Marie , who was one of the first important chemists, proved at the end of the 18th century by carefully following combustion processes by weighing that the theory was incorrect. Instead he created the theory of oxidation and the basis for further discovery of the basic laws of chemistry. For the first time, the combustion process was established through the absorption of a gas from the air, the Oxygène. Lavoisier and others also specified the first pure elements and represented them experimentally: oxygen , carbon , hydrogen , sulfur , phosphorus , a variety of metals. Lavoisier was able to show that hydrogen and oxygen combine to form water. So water was not, as long was the general belief, a chemical element, but a compound substance. Acids were considered to be non-metallic substances with oxygen. Lavoisier also formulated the law of conservation of mass in chemical reactions: In the case of material conversions, no mass is generated or destroyed . He created a new chemical nomenclature that spread rapidly. Old and difficult to understand chemical names have been replaced by modern names (e.g. sulfur liver by potassium polysulphide). Lavoisier's findings represent an important milestone in the history of chemistry ( first chemical revolution ), and compounds of substances could now be examined for the various elements. So you had to find the elements in a compound and determine the proportion of each element of a compound with a scale.

In the following period, the quantitative determinations of reactions led to the law of constant proportions ( Joseph-Louis Proust , 1794) and the suggestions of the Swedish chemist Jöns Jakob Berzelius to the development of an internationally understandable symbol notation for chemical compounds ( sum formulas and structural formulas ) and the invention of the test tube .

From Dalton to Mendeleev

Dmitri Ivanovich Mendeleev

The English naturalist John Dalton laid the foundation for a modern atomic theory in 1808 with his book A new System of Chemical Philosophy . He described the elements and their smallest indivisible unit, the atom, by specifying weight. John Dalton developed the first table on the atomic weights of elements (1805).

Joseph Louis Gay-Lussac was able to make the first atomic (molecular) weight determinations of organic gases by determining the vapor density. He also developed the first methods for organic elemental analysis and for the quantitative analysis of substances by titration . Together with Alexander von Humboldt , Gay-Lussac found gas volumes of hydrogen and oxygen of 2: 1 in the decomposition of water by electricity. The two gases could be combined again in exactly this ratio to form water.

Using a voltaic column, Humphry Davy was able to obtain sodium and potassium (1807) as new chemical elements by means of fused salt electrolysis . Davy has also proven that hydrochloric acid does not contain oxygen and therefore the presence of oxygen is not a characteristic of acids. Justus von Liebig later formulated hydrogen as the basis for the acidic property.

Jöns Jakob Berzelius had worked out a method for determining the atomic weights of metal atoms in salts. He relied on preliminary work by Jeremias Benjamin Richter . By precipitating and weighing salts, Berzelius was able to determine the atomic weights of about 40 elements. Berzelius designated atoms with the one or two letters of the corresponding Latin words, which are now used in formulas (e.g. H for hydrogenium, Fe for ferrum). Berzelius also presented a first theory of the shape of atoms after experiments with the Voltash column. He assumed that atoms must always be composed of a positive and a negative part of the charge.

For a long time there was still a lack of clarity about the atom and its equivalent weight. Dalton gave ethanol as an atom in his atomic weight table. Only much later was a distinction made between atom and molecule after considering the term equivalent . In 1811 Amedeo Avogadro put forward the thesis that the same volume of any gas contains the same number of particles. Auguste Laurent and Charles Frédéric Gerhardt were able to use this long-forgotten formulation to determine the molecular weights of organic substances by determining the gas density. The exact formulation of the distinction between atom and molecule was not made until 1858 by Stanislao Cannizzaro .

In 1869, the Russian chemist Dmitri Mendeleev and the German doctor and chemist Lothar Meyer showed that the properties of elements repeat themselves periodically when they are arranged according to increasing atomic mass - periodic table . With their theory, they were able to correctly predict the properties of as yet unknown elements .

Liebig, Wöhler, Dumas and organic chemistry

Justus von Liebig

Justus von Liebig studied with Gay-Lussac as a student and later became professor of chemistry in Giessen and Munich. Justus von Liebig founded chemistry studies in Germany with lectures and internship courses; he pioneered the interest in modern chemistry in Germany. He also had a significant influence on those interested in chemistry in Germany as editor of the journal Annalen der Pharmazie , later renamed Liebig's Annalen . Liebig improved the method of elemental analysis so that the elemental composition of organic compounds could be specified in a short time. For the first time he was able to give the molecular formula of many organic substances (chloroform, chloral, benzoic acid).

He is considered to be a pioneer in agricultural chemistry. Liebig was known that carbon dioxide gets into plants through the air. On the basis of ash analyzes of plant material, he found that potassium , phosphorus and nitrogen were constantly being removed from the soil . He advocated the use of natural fertilizers and mineral, artificially produced fertilizers in order to achieve sustainable high agricultural yields.

Liebig and Friedrich Wöhler discovered isomerism . So far, chemists have assumed that if the elemental analysis is identical, the substance should also be identical. By analyzing silver cyanates, Wöhler and Liebig were able to show that an identical elemental analysis is possible even with two chemically different substances. Wöhler was also the first to produce organic urea from an inorganic compound, ammonium cyanate, by heating . This falsified the theory of Berzelius, who assumed that organic substances can only be produced by a living organism. This synthesis of substances made Wöhler the founder of organic chemistry.

Jean Baptiste Dumas discovered another organic reaction, substitution, which was inconsistent with Berzelius' radical theory. According to Berzelius, only one electropositive particle in an organic molecule could be displaced by another electropositive particle in a molecule. Dumas had found that the electropositive hydrogen atom in acetic acid could be replaced by the electronegative chlorine atom. The diversity of reactions between inorganic and organic substances subsequently led to an increased clarification of reactions in organic chemistry.

Chemical discoveries in the 19th century

Robert Bunsen

The chemist Robert Bunsen developed the spectral analysis together with Gustav Robert Kirchhoff . With this analytical method, many new chemical elements could be discovered or detected in mineral samples on the basis of the very characteristic spectrum. Bunsen also developed the first inexpensive battery, which remained the most important type of electricity generation until Werner von Siemens developed the electrodynamics.

Hermann Kolbe recognized carbon dioxide or carbonic acid as the basic building block of many organic compounds. Replacing a hydroxyl group of carbonic acid with hydrogen or alkyl residues produces carboxylic acids, replacing two hydroxyl groups produces ketones or aldehydes. Kolbe also developed a synthesis of salicylic acid. August Wilhelm von Hofmann analyzed coal tar products and determined the molecular formula of aniline , the starting product of many later synthetic dyes. He also developed a synthetic method for the preparation of aniline from benzene. Hofmann's student, William Henry Perkin , developed the first synthetic dye, mauvein .

Friedrich August Kekulé von Stradonitz recognized that the carbon atom had four bonding valences to neighboring atoms. Chemical structural formulas found their way into chemistry, and this knowledge was very important for planning syntheses and analyzes of organic compounds. Kekulé's clarification of the structure of benzene was particularly important . Based on his knowledge of chemical structures, the chemist Adolf von Baeyer developed syntheses of the dyes indigo and phenolphthalein . Industrial chemists like Heinrich von Brunck implemented the chemists' discoveries in large-scale industry. Economically important industrial productions were the production of indigo , calcium cyanamide , the contact process for the production of sulfuric acid according to Rudolf Knietsch , the electrolytic preparation of chlorine and caustic soda .

Eugène Chevreul examined fats and fatty acids , Emil Fischer clarified the structures of sugars and carbohydrates , amino acids and peptides .

In chemical research for health improvement, the work of Louis Pasteur , the studies of fermentation and the killing of microbial pathogens through cooking ( pasteurization ), stood out; Paul Ehrlich (z. B., the discovery of staining reagents in medicine methylene blue for staining of cell nuclei and microorganisms and the diazo reaction in the urine of typhus) as well as the discovery of salvarsan , Hermann Kolbe synthesis of salicylic acid (the acetylated derivative of acetylsalicylic later than "Aspirin “Found wide application), Emil Fischer's synthesis of veronal .

Physical methods became more important in chemistry. Thomas Graham investigated diffusion processes in gases and liquids, Jacobus Henricus van 't Hoff , Svante Arrhenius and Wilhelm Ostwald discovered the dissociation of salts and acids in water. These discoveries fueled the development in electrochemistry and titrimetry , pH indication. Also, research into catalysts is an important part of the field of physical chemistry ;, the most important iron catalyst for ammonia synthesis was by Haber discovered Wilhelm Ostwald discovered the platinum catalyst for the production of nitric acid by the Ostwald method .

The chemical industry up to the First World War

Color chemistry

With the synthesis of Alizarin 1869 which until then from a large area attached madder obtained red dye, by Carl Graebe and Carl Liebermann the victory of synthetic dyes and the decline of the cultivation of plants began to dye production. Red fuchsin , first synthesized in 1858, formed the economic basis for the later Farbwerke Hoechst AG . Another important synthetic dye followed, among others, indigo , synthesized in 1878 by Adolf von Baeyer .

Up until the First World War , Germany was a leader, particularly in dye chemistry. It lost its supremacy because the patents and trademarks were expropriated during the First World War in the countries of the war opponents and a chemical industry was established there after Germany ceased to be a trading partner. The Treaty of Versailles also imposed trade restrictions.

During this time, drug development was closely linked to the dye factories and was very successful in Germany. A bestseller for many years was Salvarsan® , which has been marketed by Hoechst since 1910 , developed by Paul Ehrlich and Sahachiro Hata .

Electrochemistry

With the revolutionary idea that chemical elements exist in solution in the form of electrically charged ions , the English physicist and chemist Michael Faraday laid the basis for electrochemistry and in 1832 formulated his theory of electrolysis in his Faraday laws .

In the second half of the 19th century, electrochemical plants were built in many places where electricity was abundantly available from cheap hydropower. One example of this is Wacker-Chemie in Burghausen, Bavaria. This enabled the large-scale production of aluminum , magnesium , sodium , potassium , silicon , chlorine , calcium carbide , etc., which led to further impulses for the establishment of large chemical plants (see under Chemistry in Modern Times ).

Explosives and fertilizers

The large-scale introduction of the Haber-Bosch process for the catalytic production of ammonia from atmospheric nitrogen in 1910 as well as other redox reactions was not only of great scientific and economic importance, but also of enormous strategic importance. This enabled the production of nitric acid, which is indispensable for the production of explosives , fertilizers and dyes , in Germany without having to rely on nitric imports from overseas.

The modification of natural substances

Since around the middle of the 19th century, chemists had begun to modify natural substances through chemical processes in order to obtain inexpensive materials to replace expensive ones. Above all, cellulose modified: first result is nitrocellulose , which in the form of celluloid baleen of baleen whales replaced and as cell silk a cheap, albeit extremely flammable alternative to natural silk offered. Further developments lead to less dangerous cellulose products, e.g. B. viscose . In 1897, the substance galalith was produced from milk protein as a substitute for horn .

Many of these developments at that time took place in Germany.

Chemistry in the First World War

On the German side, in particular, the war had a major impact on the development of chemistry and the chemical industry. On the one hand, German companies (especially after the USA entered the war in 1917) lost contact with their foreign branches. For this reason, some well-known companies split into a German and an American company. This applied to the traditional trader and manufacturer of chemicals, Merck in Darmstadt, or to Röhm , the specialist for tanning chemicals , who later developed Plexiglas .

On the other hand, the shortage due to the blockade and the switch to war production forced Germany to resort to synthetic substitute products for many purposes. This applies, for example, to spices that have been replaced by flavorings produced by the chemical industry on a suitable carrier material. There was substitute pepper, which was synthetic piperine on ground hazelnut shells.

The war also prompted chemists to develop and use so-called war gases . Leading it was Fritz Haber .

In some cases, the chemical industry profited greatly from the production of essential materials such as nitric acid and explosives, as well as war gases and filters for gas masks.

Chemical industry since the First World War

After the First World War, the focus of industrial chemical development shifted from Germany more to France and the USA.

Polymer chemistry

A pioneer of polymer chemistry , often disdainfully referred to by chemists at the time as "smear chemistry ", is Hermann Staudinger , who laid the theoretical basis for this branch. In the 1930s, the first fully synthetic plastics were developed and brought into industrial production: PVC , polyvinyl acetate , nylon , perlon and rubber-like compounds ( Buna ).

The production and use of polymers (plastics) experienced a great boom soon after the Second World War , when over the years an immense variety of plastics with the most varied of properties and for the most varied of applications were created.

Synthetic fuel

The rearming National Socialist Germany in particular had great interest in synthetic motor fuel for its army. Since Germany only had small oil reserves and huge amounts of coal , the production of motor fuel from hard coal was promoted. The result is the Fischer-Tropsch synthesis and the Bergius-Pier process . This means that chemistry regains strategic importance on the eve of another war, which also applies to synthetic rubber , which was initially mainly used for the tires of military vehicles.

Insecticides and bactericides

The fight against disease-causing microbes and pests is of particular importance, as it has a profound and lasting effect on both agriculture and medicine. It is precisely in this area that the chemical industry puts enormous effort into development, but it also makes the highest profits.

With the development and production of DDT dichlorodiphenyltrichloroethane from the beginning of the 1940s, people dreamed of a complete elimination of malaria by completely eradicating the mosquitoes that transmit it . Over the course of the next 20 to 30 years, new, even more specialized insecticides are developed and brought onto the market. From around 1970 the disillusionment comes: the pests develop resistances, the insecticides, which are difficult to break down, accumulate in the food chain and put living beings at the end of the chain, like birds of prey, in danger of extinction. In addition to pollution from chemical plants, the side effects of insecticides and other agricultural chemicals are a major reason behind the rise of an environmental movement against the use of synthetic chemicals and the enactment of a DDT law that bans the production, trade and use of DDT.

With the sulfonamides , a group of potent drugs against bacterial infections of various kinds comes from the laboratories of the drug developers. The first representative of this group was Prontosil in 1935 , which was originally used as a textile dye. Here, too, more is expected of the funds from the retort than they can ultimately hold. They are effective drugs, but they can't do everything either, especially against viral infections they are ineffective.

The development of chemical theories

The law of mass action

The law of mass action , formulated by Cato Maximilian Guldberg and Peter Waage in 1864, describes the ratio of starting materials to products in chemical equilibrium. The application of this principle made it possible in many technically used reactions to better utilize the more expensive starting material by using an excess of the cheaper starting material.

Chemical kinetics

In kinetics , the laws are treated, that deal with the speed of reactions. This also includes studying the effects of catalysts, for which, in addition to his work on kinetics, Wilhelm Ostwald received the Nobel Prize in 1909 .

Attachment theories

Walter Kossel (1915) and Gilbert Newton Lewis (1916) formulated their octet rule , according to which atoms strive to acquire eight outer electrons. Bonds between ions were attributed to electrostatic attraction, atomic models flowed into the theories of binding in the form of theoretical calculations of binding forces etc.

Atomic models

The development of atomic models is closely connected to chemistry, which subject area, strictly speaking, is to be included in physics. However, new atomic models have always given new impetus to theoretical chemistry.

Quantum physics developed into its own chemical discipline, quantum chemistry , which Walter Heitler and Fritz London took its first steps in 1927 with calculations on the hydrogen atom .

Today the models are mathematically so well developed that the properties of compounds can be predicted very precisely through the distribution of electron density through very complex computer calculations.

The development of analytical technology

New knowledge and new processes in chemistry are always related to improvements in analytical technology. In addition, chemical analysis methods - wet chemical detection reactions and later instrumental analysis - have been used more and more in other disciplines of science and technology since the middle of the 19th century. At the beginning of the 21st century, chemical analysis technology is routinely used for quality assurance in numerous production processes, including those that are not of a chemical nature. In addition, the determination of the chemical composition in sciences such as geology, archeology, medicine, biology and many others plays an important role in gaining knowledge.

In the field of crime investigation , chemical analyzes began to play a role in the detection of poisoning in the first half of the 19th century . A pioneering achievement in this regard is the Marsh probe as a detection reaction for arsenic.

Qualitative analysis

The qualitative analysis is intended to answer the question: What's in it ?. Such questions have existed especially in ore smelting from the very beginning, and the beginnings of an analytical technique called "the art of experimentation" can be found there very early on.

Solder tube analyzes

The soldering tube has been used with increasing precision since the 17th century to identify minerals and estimate their metal content by means of flame coloration and precipitation on charcoal. The stronghold of this analytical technology, which can be assigned to metallurgy, was Freiberg with its rich ore mining.

Wet chemical processes

Wet chemical processes got under way intensively in the course of the 19th century. In the field of inorganic analysis, the elements contained in the sample are detected by systematic precipitation in the cation separation process and by suitable color reactions. Corresponding procedures have been developed for anions.

The qualitative analysis of organic substances required a great deal of experience in the field of color reactions, as many substances produced similar color reactions. The processes could be made more and more sensitive by the further development of laboratory equipment and by ever purer reagents , so that both the size of the necessary sample quantities became smaller and smaller, and the detectable concentration fell further and further.

Physical procedures

Physical processes (flame coloring) were used to identify elements from the very beginning of the art of tasting. With the expansion of spectroscopic methods in the areas of ultraviolet, visible, infrared and X-ray radiation, the identification of substances has become more reliable, more precise and faster. Qualitative and quantitative determinations can be combined very well here, just like with chromatographic methods.

Quantitative analysis

Only through the use of precise measuring instruments (especially scales) and quantitative analytical methods was it possible to develop from alchemy as a natural science since the 17th and 18th centuries. Advances in the accuracy and sensitivity of quantitative analyzes with the aim of the most precise content information are therefore always associated with the further development of devices for measuring mass and volume. This often led to the discovery of new chemical elements, compounds and reactions.

Gravimetry

The gravimetry , so quantitation with a delicate balance, can well as the addressed method of analysis of the 19th century. The search was for reliable reactions in which the amount of products is not only theoretically but also practically in a clear relationship to the starting material to be determined. A classic example of this method is the determination of the chloride content by precipitating with silver nitrate and weighing the dried precipitate of silver chloride . Even with the elemental analysis gravimetry plays an important role, for. B. with the help of the five-ball apparatus developed by Liebig .

Gravimetric methods are cumbersome and slow, albeit very accurate. The necessary filtration, washing and drying after the precipitation reaction took hours to days, depending on the substance. Therefore, the search was on for faster processes, which are particularly sought after in the quality control of industrial chemical production.

With electrogravimetry , the process of electrolysis was introduced around the beginning of the 20th century as a process for the clean separation of metals from the solutions of their ions, which were then weighed.

Volumetry

Gravimetry allowed very precise analysis results, but was time-consuming and costly to carry out. As the chemical industry flourished, the demand for faster, yet more accurate analysis methods grew. The measurement of the volume of a reagent solution of known content ( standard solution ) could often replace a gravimetric determination. With such a titration , the substance to be determined must react quickly and clearly with the standard solution. The end of the reaction must be recognizable. Color indicators are often used for this. The scales were now only used to produce the custom-made solution. Such volumetric (titrimetric) methods appeared as early as the end of the 18th century. They developed from semi-quantitative tasting methods, for example for determining the quality of wine vinegar . Here, soda powder was added to a measured vinegar sample until no further foaming (carbon dioxide formation) occurred. The more soda was consumed, the better the vinegar was. One of the first very precise titration methods was the chloride determination according to Gay-Lussac (clear point titration with silver nitrate solution ). Titrations became more widespread when crucial practical improvements were made. The Mohr burette with pinch cock made it possible to dose the standard solution easily and precisely. During the 19th and 20th centuries, many different types of reactions were made available for titration. In addition to the long-known precipitation and acid-base titrations, this also included redox and complex titrations.

Chromatographic methods

The Russian botanist Michail Semjonowitsch Zwet reported in 1903 that dissolved substances can be separated by flowing through a column filled with an adsorbent. The method did not gain increased attention until the 1930s, but then led to a large number of methods that are suitable for qualitative and quantitative determinations of numerous substances from mixtures: paper chromatography , gas chromatography , high pressure liquid chromatography , gel permeation chromatography , thin layer chromatography , ion exchange chromatography , electrophoresis .

Such methods revolutionized the analysis of complex mixtures. A comprehensive analysis was often only possible with a chromatographic method. In all cases, chromatography accelerated and made the work of the analytical laboratories cheaper and faster, thereby making a considerable expansion of food controls and doping controls as well as more precise process monitoring of numerous production processes as routine measures practically possible.

Another quality leap in the second half of the 20th century was the combination of chromatographic separation processes with spectroscopic identification processes such as mass spectrometry , infrared spectroscopy and others.

Automation of analysis processes

Since the development of electronic data processing, analysis processes have been automated more and more. Volumetric, spectroscopic and chromatographic methods are particularly suitable for this. The automation led to a significant increase in the capacity of the analysis laboratories and to a reduction in costs. This meant that more analyzes could be carried out for control and monitoring purposes. The automation of analytical procedures has made a major contribution to expanding food controls, doping controls, clinical blood and tissue tests, etc. and making them an everyday control tool. Significantly larger sample series could also be analyzed in research and thus more reliable statements could be made, for example about the dependencies of active ingredient contents in plants or about mineralogical connections. In addition, the automation led to a further improvement of the measurement accuracy through more precise compliance with conditions, especially when taking and applying samples.

The development of laboratory equipment

Laboratory of the chemical institute of the University of Leipzig (1906)

The equipment of the laboratories played an important role, both for the possibilities of analysis and for the production of substances on a small scale. Initially, only small charcoal stoves were available for heating, which were difficult to regulate and cumbersome to use. With the introduction of luminous gas in cities and the invention of the Bunsen burner , an uncomplicated and easy-to-regulate way of heating became available. The invention of the vulcanization of rubber by Charles Goodyear plays an important role here, since it made rubber hoses available as flexible gas lines. Again and again, developments in chemistry made it possible to further develop laboratory equipment, which in turn led to further progress in chemistry. A further step towards precise temperature control are the electric patio heaters and thermostated water baths, which have reached their climax so far in a computer-controlled reaction system using thermosensors and controlled electric heating.

Glass appliances were originally thick-walled and bulky. This was a major reason why large amounts of material were required for analyzes. With the introduction of the gas flame in glass-blowing and the further development of the composition of the glasses, laboratory devices could be manufactured ever smaller, thinner-walled and in more complex shapes. The resulting variety of devices developed from practice helped significantly in reducing the quantities to be analyzed and in being able to carry out increasingly complex processes in practice for the production of substances. With the introduction of the standard cut for glass appliances in the second half of the 20th century, the now industrially manufactured individual parts were easily interchangeable and allowed very complex, specialized test arrangements to be set up with little expenditure of time.

More and more plastics found their way into chemical laboratories and made work easier. While unbreakable, chemical-resistant vessels were made of cardboard soaked with paraffin in the 19th century, many modern laboratory devices are made of polyethylene, polypropylene, polystyrene, polycarbonate and, for particularly good resistance to acids and alkalis and with a very easy-to-clean surface, made of polytetrafluoroethylene ( Teflon ) . The introduction of lightweight, inexpensive to manufacture plastic devices led to the increasing use of disposable devices. This eliminated the risk of contamination with residues from previous work and further increased the reliability and sensitivity of analyzes.

With the advent of electrical devices in technology from the beginning of the 20th century, the chemical laboratory also benefited from electrical stirrers, shakers, mills, pumps, etc., which made work much easier. The next step is controlled devices that can be programmed over time. This made personal monitoring, especially of long processes with parameter changes, unnecessary.

Social reactions against the penetration of chemistry in any area

Beginning in the 19th century, chemistry became an increasingly important economic and social factor. The role of chemistry, especially the chemical industry, with its downsides was repeatedly discussed with different focuses. On the other hand, chemistry changed the external appearance of people and buildings through new substances, think of paints and plastics, for example.

Occupational safety

The first social reaction concerned the poor working conditions in the chemical industry in the early days, which led to serious illnesses among chemical workers. This was not always due to the indifference of entrepreneurs; the dangers posed by the new substances were mostly still unknown. Work safety regulations were enacted towards the end of the 19th century that reduced the dangers. This also included regular medical examinations. With the introduction of ever better closed processes and ever better personal safety equipment in industry, the risks from inhalation, ingestion or absorption through the skin have decreased significantly.

A second risk in the chemical industry is the risk of accidents and fire, which is still there. With better and better preventive fire protection, to which the deeper and deeper chemical knowledge makes a significant contribution, and with more and more trained and equipped fire brigades with more and more chemical knowledge, the risk could be reduced further, but never completely eliminated, as spectacular chemical accidents in recent years show. Chemical accidents such as the fish deaths caused by cyanide in the Tisza or the approximately 8,000 deaths (another 20,000 from the long-term effects) in Bhopal , like other accidents, led to heated discussions about the risks of a chemical industry.

Emissions and waste

In the early days of the chemical industry, the potential for environmental damage from sewage and emissions with the exhaust air was greatly underestimated. The first step in improving the situation was to raise the chimneys so that the pollutants could spread over a wider area in the earth's atmosphere and thus dilute them. Only in the second half of the 20th century did a rethink gradually begin - not only with regard to agricultural pesticides , privately emitted tobacco smoke and excess detergent phosphates. A growing environmental movement increasingly forced industry from around 1970 to purify wastewater and exhaust air and thus minimize pollutant emissions.

Organic movement

After the chemical industry was praised as a savior in agriculture up to the middle of the 20th century and also had considerable successes in increasing yields, an initially growing movement emerged from around 1970, culminating in the founding of so-called green parties . This movement fought against the increasing proportion of synthetic substances used by the chemical industry in agriculture as fertilizers , growth promoters , animal medicines, pesticides , etc.

The green movement also took on food production and denounced not only chemically supported plant and animal production, but also the use of artificial substances as ingredients or additives for food. As a counter-reaction to large-scale industrial production in agriculture and food production with the strong influence of chemical methods and artificial substances, the ecological movement demands that natural cycles be observed with only gentle human intervention and the complete abandonment of the introduction of artificial substances into the biological cycle. A corresponding resource and environmentally friendly flow in chemistry is called green chemistry .

See also

literature

Books

  • Bernadette Bensaude-Vincent , Isabelle Stengers : A history of chemistry. Harvard University Press, 1996. (French original La Decouverte 1993)
  • William Hodson Brock : Vieweg's History of Chemistry. Vieweg, Wiesbaden 1997, ISBN 3-540-67033-5 . (Original title in Great Britain: The Fontana History of Chemistry. 1992, in USA Norton History of Chemistry )
  • Günther Bugge (ed.): The book of the great chemists. Volume 1, 2, Verlag Chemie, Weinheim 1974, ISBN 3-527-25021-2 . (Reprint of the edition published by Verlag Chemie, Berlin, 2 volumes, 1929, 1930)
  • Maurice Crosland : Historical studies in the language of chemistry. Harvard University Press, 1962, 1978.
  • Michael Wächter: Brief history (s) of the discovery of chemistry in the context of contemporary history and natural sciences , Verlag Königshausen und Neumann, Würzburg 2018, ISBN 978-3-8260-6510-1
  • Kostas Gavroglu, Ana Simoes: Neither physics nor chemistry. A history of quantum chemistry. MIT Press, 2012.
  • Arthur Greenberg: Twentieth Century-Science: Chemistry Decade by Decade. Facts on File, 2007.
  • Arthur Greenberg: From Alchemy to Chemistry in Picture and Story. Wiley, 2007.
  • Aaron J. Ihde : The development of modern chemistry. Harper and Row, New York 1964. (Dover 2012)
  • Eberhard Schmauderer (Ed.): The chemist through the ages. Verlag Chemie, Weinheim 1973, ISBN 3-527-25518-4 .
  • Otto Krätz : 7000 years of chemistry. Alchemy, the black art - black powder - explosives - tar chemistry - paints - plastics - biochemistry and more; from the beginnings in the ancient Orient to the latest developments in the 20th century. Nikol, Hamburg 1999, ISBN 3-933203-20-1 . (First edition as: Fascination Chemistry . 7000 years of teaching materials and processes. Callwey, Munich 1990, ISBN 3-7667-0984-4 )
  • Keith J. Laidler : The World of Physical Chemistry. Oxford University Press, 1993.
  • Henry M. Leicester : The Historical Background of Chemistry. Wiley, 1956. (Dover 1971) (Archives)
  • Henry M. Leicester, Herbert S. Klickstein: A Source Book in Chemistry 1400-1900. Harvard University Press, 1952. (4th edition 1968)
  • Henry M. Leicester: A Source Book in Chemistry 1900-1950. Harvard University Press, 1968.
  • Georg Lockemann: History of Chemistry. Walter de Gruyter & Co., Berlin 1953.
  • Derek B. Lowe: The Chemistry Book. From gunpowder to graphs. 250 Milestones in the History of Chemistry , Librero 2017 (Original: The Chemistry Book , New York: Sterling Publ., 2016)
  • Robert Multhauf : The Origins of Chemistry. Oldbourne, London 1966. (The Watts, New York 1967, 1993)
  • Dieter Osteroth: Soda, tar and sulfuric acid: the way to large-scale chemistry. Rowohlt, Reinbek near Hamburg 1985.
  • James Riddick Partington : A short history of chemistry. 3. Edition. London / New York 1960.
  • JR Partington : A History of Chemistry. MacMillan, 1970 (Volume 1), 1961 (Volume 2), 1962 (Volume 3), 1964 (Volume 4).
  • Winfried R. Pötsch, Annelore Fischer, Wolfgang Müller: Lexicon of important chemists . With the collaboration of Heinz Cassebaum. Bibliographisches Institut, Leipzig 1988, ISBN 3-323-00185-0 .
  • Claus Priesner : Illustrated history of chemistry. Theiss, 2015.
  • Ernst F. Schwenk: Great moments in chemistry. From Johann Rudolph Glauber to Justus von Liebig. Verlag CH Beck, Munich 1998, ISBN 3-406-42052-4 .
  • Günther Simon: A brief history of chemistry. (= Practical series, chemistry department. 35). Cologne 1980.
  • Irene Strube , Rüdiger Stolz, Horst Remane : History of Chemistry: An Overview from the Beginnings to the Present. DVW, Berlin 1986. (2nd edition, ibid. 1988)
  • Wilhelm Strube : The historical path of chemistry. Volume I: From prehistoric times to the industrial revolution. 4th edition. German publishing house for basic industry, Leipzig 1984, DNB 850275016 .
  • Ferenc Szabadváry : History of Analytical Chemistry. Vieweg, 1985.
  • Wolfgang Schneider : History of Pharmaceutical Chemistry. Verlag Chemie, Weinheim 1972.
  • Lucien F. Trueb: The chemical elements. A journey through the periodic table. S. Hirzel Verlag, Stuttgart 2005, ISBN 3-7776-1356-8 .
  • Mary Elvira Weeks : Discovery of the Elements. 6th edition. Publisher Journal of Chemical Education, 1956. (Archives)
  • Helmut Werner : History of Inorganic Chemistry. The development of a science in Germany from Döbereiner to today. Wiley-VCH, 2016, ISBN 978-3-527-33887-0 .
  • Jost Weyer : History of Chemistry. Volume 1: Antiquity, Middle Ages, 16th to 18th centuries. Springer Spectrum, Wiesbaden 2018. doi: 10.1007 / 978-3-662-55798-3 .
  • Jost Weyer: History of Chemistry Volume 2 - 19th and 20th centuries. Springer Spectrum, Wiesbaden 2018. doi: 10.1007 / 978-3-662-55802-7 .

Older literature:

  • Marcelin Berthelot : La chimie au moyen age. 4 volumes. Paris from 1889.
  • James Campbell Brown : A history of chemistry from the earliest times. 2nd Edition. Churchill, London 1920. (Archives)
  • Eduard Färber : The historical development of chemistry. Springer, Berlin 1921. (Archive)
  • Carl Graebe : History of Organic Chemistry. Julius Springer, 1920.
  • Hermann Kopp : History of Chemistry. 4 volumes. Braunschweig 1843–1847. (Reprint Hildesheim 1966)
  • Hermann Kopp: Contributions to the history of chemistry. Braunschweig 1869–1875.
  • Edmund Oskar von Lippmann : Time tables on the history of organic chemistry. Springer, Berlin 1921.
  • Ernst von Meyer : The history of chemistry from the oldest times to the present. 1899. (3rd edition 1914)
  • Paul Walden : History of Organic Chemistry since 1880. Julius Springer, Berlin 1941. (Reprint 1990)
  • Paul Walden: Measure, Number and Weight in the Chemistry of the Past. A chapter from the prehistory of the so-called quantitative age of chemistry. (= Collection of chemical and chemical-technical lectures. New series, 8). Stuttgart 1931.
  • Paul Walden: Chronological overview tables on the history of chemistry from the oldest times to the present. Berlin / Göttingen / Heidelberg 1952.

For literature on alchemy see there

Essays

Web links

Wikisource: Chemistry  - Sources and full texts

Individual evidence

  1. ↑ Journal Angew. Chem. 1903, p. 267.
  2. ^ Michael Rostovtzeff: Social and economic history of the Hellenistic world. Volume 2, Darmstadt 1998, p. 984.
  3. ↑ Joachim Telle: Alchemie II. In: Theologische Realenzyklopädie. Volume 2, de Gruyter, 1978, p. 208.
  4. ↑ Berend Strahlmann: Chymists in the Renaissance. In: Eberhard Schmauderer (Hrsg.): The chemist in the course of time. Verlag Chemie, Weinheim 1973, p. 54.
  5. ↑ A useful bergbuchleyn, (1500).
  6. ↑ Probirbüchlin / vff Golt, silver / copper / lead / and all the same common use too well ordered (1518).
  7. ↑ Dietlinde Goltz: Attempt to draw the line between "chemistry" and "alchemy". In: Sudhoff's archive. 52, 1968, pp. 30-47.