Chemistry (Encyclopedia of Science)

Chemistry is the study of the composition of matter and the changes that take place in that composition. If you place a bar of iron outside your window, the iron will soon begin to rust. If you pour vinegar on baking soda, the mixture fizzes. If you hold a sugar cube over a flame, the sugar begins to turn brown and give off steam. The goal of chemistry is to understand the composition of substances such as iron, vinegar, baking soda, and sugar and to understand what happens during the changes described here.


Both the term chemistry and the subject itself grew out of an earlier field of study known as alchemy. Alchemy has been described as a kind of pre-chemistry, in which scholars studied the nature of matterut without the formal scientific approach that modern chemists use. The term alchemy is probably based on the Arabic name for Egypt, al-Kimia, or the "black country."

Ancient scholars learned a great deal about matter, usually by trial- and-error methods. For example, the Egyptians mastered many technical procedures such as making different types of metals, manufacturing colored glass, dying cloth, and extracting oils from plants. Alchemists of the Middle Ages (400450) discovered a number of elements and compounds and perfected other chemical techniques, such as distillation (purifying a liquid) and crystallization...

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Chemistry (Encyclopedia of Science and Religion)

When, in the 1830s, eight authors published Bridgewater Treatises on the goodness and wisdom of God, the series included volumes on astronomy and physics, geology, psychology, human physiology, animal and vegetable physiology, zoology, and the human hand. But chemistry was stuffed into a rag-bag of a book by William Prout (1785850) that also covered meteorology and the function of digestion. Yet this was a time when lectures on chemistry attracted large and enthusiastic audiences, and chemistry was perceived as a fundamental science. When most science was popularized in a context of natural theology, why was chemistry seen as problematic?

In the early twenty-first century, chemicals are perceived as alarming additives, the chemical industry as a source of pollution, and fertilizers, pesticides, and explosives as dangerous to the planet and its populations. Still, people depend upon plastics, synthetic fibers, pharmaceutical drugs, and paints. Chemistry is everybody's service science, ubiquitous, but highly suspect, which points to the reason for its neglect by natural theologians. Astronomers contemplate the starry heavens; chemists understand the world in order to change it.

Chemical theology in history

The alchemist was an optimist, seeing potential gold where others saw dross. Alchemists often identified the perfecting of base metal into gold with the simultaneous spiritual perfecting of the alchemical practitioner. George Herbert's well-known poem The Elixir (1633) is indeed used as a hymn. God's creation of the cosmos from chaos was compared to an alchemical project. In the laboratory, the natural improvement of base metals could be accelerated. But in the second half of the seventeenth century Robert Boyle, one of the fathers of modern chemistry, although deeply interested and involved in alchemy, delighted especially in the mechanical or corpuscular philosophy as a basis for natural theologyomparing God to a clockmaker rather than to an alchemist. He and the other founders of the Royal Society favored the plain words of artisans rather than witty metaphysical conceits or coded messages for initiates. The oblique, resonant, and metaphorical language of alchemy gave way, especially in the 1780s in the hands of chemist Antoine Lavoisier, to sober prose approximating as far as possible to algebra. For Boyle, who was deeply devout, mechanical explanations were particularly satisfying and intelligible. He bequeathed money for lectures demonstrating the existence and wisdom of God. For succeeding generations this meant astrotheology, joyfully dwelling upon Isaac Newton's work, and physico-theology, showing how humans and other creatures were like beautifully designed little clocks living in an enormous clock.

Whereas astronomy was a science of meditative observation and calculation (with spin-offs into calendars and navigation), chemistry was active and practical. The busy chemist's task was to improve the world by isolating metals, distilling medicines, or making ceramics and dyes. Adam and Eve had been expelled from paradise and sentenced to hard labor: Chemists might be able to do something about that. As the macho English chemist Humphry Davy declared in the early nineteenth century, the chemist is godlike because he exerts a "creative energy" that "entitles him to the distinction of being made in the image of God and animated by a spark of the divine mind" (p. 361). Instead of simply commending this best of all possible worlds and its designer, therefore, chemists seek to understand it in order to change it for the better, using God-given intelligence and manual skills.

Chemistry is essentially an experimental science, concerned with the secondary qualities of color, taste, and smell, and demanding trained fingers, hands, and noses; it cannot be done on paper in an armchair in a study or library. When interrogating nature through experiments, the chemist for Davy is not a passive scholar, but a master, active with his own instruments, exerting the "godlike faculties, by which reason ultimately approaches to inspiration." In the words of a poet, Davy's lectures disclosed "Nature's coyest secrets." Davy was a friend of Samuel Taylor Coleridge and other Romantic poets, and went from interrogation to worship of nature, as we see in his poems and last writings. Such pantheism was not unusual among scientists of the nineteenth century, who found religious experience in communing with nature both in the laboratory and on mountain tops.

The enthusiastic Samuel Parkes, a Unitarian and a chemical manufacturer, borrowing from church teaching called his elementary and successful book of 1806 The Chemical Catechism. Not only did he hope that parents would ensure that their children learned chemistry for its utility, he also sought to defend the youthful mind against "immorality, irreligion, and scepticism." The text (questions and answers) was amplified with footnotes, where chemical detail, poetry, and occasional encomia upon the creator were to be found. The "goodness of the ALMIGHTY" was particularly displayed in the various uses to which different substances may be put, though sometimes the "design of Nature" in assigning properties to things was not yet apparent. The book is pervaded with natural theology, rather than being an exposition of it. In a later popular work The Chemistry of Common Life (1855), widely known in translation as well as in English, the Presbyterian James Johnston concluded surprisingly that earthly life was insignificant in the vast general system of the universe. Humans were here solely because God, in a separate act of will, had formed beings to admire God's work. Johnston sought thus to indicate the insufficiency of natural theology without revelation, which told more of God's purposes and character than could ever be inferred from chemical discoveries.

Authors of Bridgewater Treatises were meant to confine themselves to natural theology, and Prout's was thus a straightforward exposition of the design argument, given a particular turn because of his idiosyncratic atomic theory. But chemistry was making rapid progress, and in 1844 George Fownes published his book Chemistry as Exemplifying the Wisdom and Benevolence of God, which was awarded the Actonian Prize associated with the Royal Institution, where Davy and Michael Faraday held forth. Fownes began from the position that recent studies (especially with microscopes, enormously improved at this time) had shown how exquisitely animals were adapted to their environment. Then he declared that recent discoveries in chemistry, especially in its organic branch, made it easier to use science to infer design. He urged people to look for God's activity in the commonplace and the everyday world, seeing God's hand in the simple laws of chemical combination, the ubiquity of protein, and the equilibria among reversible reactions that made animal and plant chemistry possible. Natural theology was for Fownes the highest aim of science. His book is also a good account of the current state of chemistry, being transformed at that time through the work especially of Justus Liebig, in whose wake German universities were training large numbers of professional research chemists to work in industry and academia.

Both Prout and Fownes came under friendly fire from George Wilson in his Religio Chemici (published posthumously in 1862) for their Panglossian emphasis upon unmixed and unbounded benevolence. Wilson, the first Professor of Technology in Edinburgh University in Scotland, was dogged by bereavements and illness, but supported by staunch religious faith. He believed that while chemical evidence, especially from the earth's atmosphere and the carbon and water cycles, demonstrated design, the demonstration of benevolence was another story. Introducing a gendered perspective, he noted that men read the Bridgewater Treatises and such books chiefly to learn science; women, more perceptive, did not because they were not impressed by such banal optimism. The problem of evil was real, and the dark side must be faced. If human bodies are constantly being renewed, why then do they wear out? Why are there poisons? Wilson noted the formidable weapons of destruction possessed by carnivoresGod has been very kind to the shark"nd the reality and enduring character of pain, animal and human. Evil exists alongside good, and cannot in the manner of the Manicheans be separated from it. Chemistry can show that God has love, but not that God is love. For Wilson the problem of evil is real and cannot be solved in this world, except in the light of revealed religion and true conversion. Astrotheology might be immune from such criticisms, but physico-theology along with reasoning from chemistry is undoubtedly undermined. Most of those writing natural theology had been, like William Paley, healthier and wealthier than the average person, and Wilson brought in a draft of fresh air.

The twentieth century onwards

Natural theology had made popular chemical books and lectures interesting and indeed momentous. By 1900, however, there were many students (more than in any other science) with examinations to pass and professional qualifications to gain, and their textbooks had become much drier and more factual, presenting chemical theory but not a worldview. Also, natural theology was in retreat for most of the twentieth century, under assault not only from scientific naturalists but also from theologians. And whereas chemistry had seemed a fundamental science to Davy and his contemporaries, in the early twentieth century it appeared that chemistry was being reduced to physics with the work of Ernest Rutherford and Niels Bohr. No doubt experiment was still necessary because the mathematical equations, based upon quantum theory, were too difficult to solve in detail, but genuine chemical explanation would in principle be in terms of physics, or so it seemed to physicists, who enjoyed enormous prestige. Philosophy of science, therefore, was for much of that century focused upon physics; chemistry seemed necessary, but not exciting. In addition, much nineteenth-century research had been done by individuals. In the twentieth century, the teams and groups that now undertook scientific research needed to include a chemist or two whatever their field, but the glamorous science was physics. Then came the elucidation of the DNA structure, making molecular biology and genetics major areas of interest; here, as in pharmacy, chemistry was essential, but still not the center of interest for the lay person following what was going on. In the United States, Creationism focused the attention of natural theologians upon Charles Darwin's theory of evolution by natural selection, which by the second half of the century incorporated genetics. Only perhaps in the context of ecotheology has chemistry again impinged seriously on religious thinking.

Nevertheless, chemistry was not really reduced to physics any more than architecture has been; builders must take into account the law of gravity, and chemists building molecules cannot defy the laws of physics. Working within such constraints is the basis of art in both fields. Roald Hoffmann emphasizes the creativity that lies behind structural chemistry, designing substances never made before. He also draws attention to the visual and verbal language of chemistry and the role of illustration in the science. Lavoisier's project of abolishing richness has not been achieved, and chemistry can be fun. Hoffmann has also been involved with Shira Schmidt in reflection on Jewish traditions in the light of chemistry, seeing argument as central to both and exploring dichotomies between natural and artificial, symmetry and asymmetry, purity and impurity. This is not the traditional enterprise of natural theology, as in Fownes's book, but much less formal. For the believer, satisfying parallels and analogies reveal themselves in a coherent pattern, and metaphors are refreshed.

A collective study of Science in Theistic Contexts (2001) unsurprisingly contains no discussion of chemistry. In their Gifford Lectures, however, published as Reconstructing Nature (1998), John Brooke and Geoffrey Cantor investigate the engagement (a useful word with multiple meanings) of science with religion in a historical perspective. They devote a chapter to chemistry, with particular discussion of the theological problems that can arise from the idea that the chemist is perfecting creation. They see process as a feature of chemistry that might bear upon religion. Most people accept that a world with nylon and aluminum is better than one without, and expect more progress in applied chemistry, but people remain uneasy about nineteenth-century chemist Eleanor Ormerod's enthusiastic espousal of chemical pest-control, with its aim of exterminating noxious insects. Brooke and Cantor also look at materialism and reductionism, in which chemistry has been involvedhe melancholy may be bracingly told "it's just your chemistry," and may or may not find that consoling.

What emerges is that chemistry has never been nearly as tempting for the natural theologian, wishing to put design beyond reasonable doubt, as astronomy or natural history. While the world of stinks and bangs is fun, atoms and molecules lack sublimity or accessibility. Chemistry is not only the experimental science par excellence, it is also useful in seeking to improve the world and the quality of life. That, and the idea of process, is something that should resonate with anyone pursuing natural theology, especially in an intellectual climate where the argument from design runs up against a deep prevailing skepticism. In such a broader and more sensitive natural theology, there should also be room for the metaphors and analogies from chemistry that can make it aesthetically, rather than logically, compelling.



Boyle, Robert. The Vulgar Notion of Nature (1686), ed. M. Hunter. Cambridge, UK: Cambridge University Press, 1996.

Brock, William H. From Protyle to Proton: William Prout and the Nature of Matter, 1785985. Bristol, UK: Adam Hilger, 1985.

Brooke, John H., and Cantor, Geoffrey. Reconstructing Nature: the Engagement of Science and Religion. Edinburgh, UK: T&T Clark, 1998.

Brooke, John H.; Osler, Margaret J.; and Van der Meer, Jitse M., eds. Science in Theistic Contexts: Cognitive Dimensions. Chicago: University of Chicago Press, 2001.

Davy, Humphry. Collected Works, Vol. 9. London: Smith Elder, 1839840.

Fownes, George. Chemistry, as Exemplifying the Wisdom and Beneficence of God. London: John Churchill, 1844.

Hoffmann, Roald, and Schmidt, Shira Leibowitz. Old Wine, New Flasks: Reflections on Science and Jewish Tradition. New York: W. H. Freeman, 1997.

Hoffmann, Roald, and Torrence, Vivian. Chemistry Imagined: Reflections on Science. Washington, D.C.: Smithsonian, 1993.

Johnston, James F.W. The Chemistry of Common Life. Edinburgh, Scotland: Blackwood, 1855.

Knight, David M. Ideas in Chemistry: A History of the Science, 2nd edition. London: Athlone Press, 1995.

Knight, David M. "Higher Pantheism." Zygon 35 (2000): 60312.

Knight, David M., and Kragh, Helge eds. The Making of the Chemist: The Social History of Chemistry in Europe 1789914. Cambridge, UK: Cambridge University Press, 1998.

Lundgren, Anders, and Bensaude-Vincent, Bernadette, eds. Communicating Chemistry: Textbooks and their Audiences 1789939. Canton, Mass.: Science History Publications, 2000.

Nye, Mary Jo. Before Big Science: The Pursuit of Modern Chemistry and Physics 1800940. New York: Twayne, 1996.

Parkes, Samuel. The Chemical Catechism, with Notes, Illustrations and Experiments, 3rd edition. London: Lackington Allen, 1808.

Prout, William. Chemistry, Meteorology, and the Function of Digestion, Considered With Reference to Natural Theology. London: William Pickering, 1834.

Topham, Jonathan R. "Beyond the 'Common Context': The Production and Reading of the Bridgewater Treatises." Isis 89 (1998): 23362.

Wilson, George. Religio Chemici: Essays. London: Macmillan, 1862.


Chemistry (World of Earth Science)

Chemistry deals with the study of the properties and reactions of atoms and molecules. In particular, chemistry deals with reaction processes and the energy transition. Major divisions of chemistry include inorganic chemistry, organic chemistry (chemistry of carbon based compounds), physical chemistry, analytical chemistry, and biochemistry. Geochemistry deals with the reaction unique to geological processes.

The origin of the modern science of chemistry is often attributed to the work of French physicist and chemist Antoine Lavoisier (1743794). In 1774, Lavoisier demonstrated that oxygen is a critical component of air needed for combustion. This observation led into a better understanding of the changes in composition and structure of matter. Lavoisier's publication of the first list of elemental substances eventually evolved into the Periodic table of the elements. Other important contributions to early chemistry include British chemist and physicist John Dalton's (1766844) atomic theory; Italian physicist and chemist Amedeo Avogadro's (1776856) theory that molecules are made up of atoms; and Sir Edward Frankland's (1825899) descriptions of chemical reactions. These observations and theories all led to the portrayal of chemistry as the architecture of molecules.

Each discipline of chemistry (e.g., inorganic, analytical, physical chemistry, etc.) studies a different facet of the structure and composition of materials and their changes in composition and energy. As molecules and scientific problems become more complex, the traditional areas of chemical investigation begin to overlap with other physical sciences.

Organic chemistry is the study of compounds that contain carbon atoms. The term organic was first introduced by the Swedish scientist, Jöns Jacob Berzelius (1779848) to refer to substances isolated from living systems. Inorganic compounds, a call predominant in geological processes, are those isolated from nonliving sources. At the time, it was believed that a "vital force" only present in living systems was necessary for the preparation of organic compounds. In 1828, German chemist Friedrich Wöhler (1800882) first synthesized urea, an organic compound isolated from urine, by evaporating a water solution of the inorganic compound ammonium cyanate. Eventually, the vital force theories (e.g., those based on the idea that life and the chemistry of life depended upon an undefined vital force peculiar to living organisms) were discarded and organic chemistry became the investigation of the over seven million carbon-containing compounds. Today, organic chemists work primarily to synthesize new molecules to be used in pharmaceuticals, surfactants, paints, and coatings. They are also involved in scaling reactions from grams to tons in industrial research laboratories.

Inorganic compounds, at the time of the vital force theories, were those materials isolated from nonliving sources. Now, inorganic chemistry is the chemistry of all the elements except for carbon. This includes the chemistry of transition metals which coordinate with organic ligands and make up hemoglobin; the very reactive alkali metals used to make organometallic compounds in the manufacture of pharmaceutical materials; and also, the semi-metallic elements that have unusual electronic properties used in solar cells for the conversion of light into electricity. Inorganic chemists find employment in the production of glass, ceramics, semi-conductors, and advanced synthetic catalysts.

In 1909, German scientist Wilhelm Ostwald (1853932) was awarded the Nobel Prize in Chemistry for his work with catalysis, a very useful technique in industrial manufacturing. Ostwald is often referred to as the father of physical chemistry, a branch of chemistry devoted to the investigation of the underlying physical processes responsible for chemical properties and phenomena. Physical chemistry describes the influence of temperature, pressure, concentration, and catalyst used in organic and inorganic reactions. These data give important insight into the mechanisms of the chemical change and predict the best experimental methodology for a specific manufacturing process. Physical chemists are employed in industrial, academic, and governmental laboratories to study and calculate the fundamental properties of elements and molecular compounds. The application of physical chemistry is critical to the development of efficient devices, new applications of chemicals and better methods for measuring chemical phenomena.

Analytical chemistry is the branch of chemistry involved with the measurement and characterization of materials. Chemical analysis is divided into classical and instrumental methods. Wet or classical chemical analysis is the oldest form of analytical chemistry and involves the use of chemical reactions utilizing gravimetric and volumetric methodology to analyze material compositions. The use of instrumental methods for analytical analysis provides comprehensive information about chemical structure. Instrumental techniques include methods for measuring molecular spectroscopy such as infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), mass spectroscopy (MS), and x-ray crystallography. Gas chromatography, liquid chromatography, and electrophoresis are examples of separation methods used by analytical chemists. There is a need for analytical chemists in governmental, industrial, and academic research organizations to characterize new materials and determine the chemical composition of materials.

Chemists often work with geologists and geophysicists, in an effort to identify specific geologic reactions or to help characterize a specific geologic formation.

See also Atmospheric chemistry; Bowen's reaction series; Dating methods; Petroleum detection; Petroleum, economic uses of; Petroleum extraction; Weathering and weathering series