The Chemical Wizards

Dr. Sarfaraz K Niazi (e-mail: niazi@niazi.com)

Nothing has fascinated man more than his discovery of fire. The first chemist was born when man burned wood to convert cellulose fibre into charcoal. From thereon it was food cooking, firing of pottery and bricks and working with metals; civilizations of China, Mesopotamia and Egypt followed. Early theoretical explanations of chemical phenomena were generally magical and mythological in character. Aristotle, in the 4th century BC, formulated a theory of "four elements" that control all chemical reactions. This theory of matter that dominated scientific thinking for almost 2,000 years. Alchemy, the next major phase of the history of chemistry, developed in Alexandria, Egypt, and combined aspects of Greek philosophy, Oriental artisanship, and religious mysticism. Its main objective was the transformation of base metals into gold. This Arabic alchemy came into Western Europe between the 11th and 16th centuries through Sicily and Spain. The mystical ideas so introduced were accompanied by practical advances in chemical procedures, such as distillation, and by the discovery of new metals and compounds. The art of metallurgy became more sophisticated; chemicals were introduced into medical practice by Paracelsus in the 16th century.

At the beginning of the 17th century chemistry became recognized as a science. The first methodical chemical textbook, Alchemia, by Andreas Libavius, was published in 1597. Alchemia was defined as the art of producing reagents and extracting pure essences from mixtures. Lavoisier, the father of modern chemistry, defined a chemical element as a substance that could not be decomposed into simpler substances by heat or chemical reaction. The atomic theory of John Dalton, at the beginning of the 19th century, further extended Lavoisier's theories. Dalton suggested that each element was composed of very small particles, called atoms, which have a characteristic weight, and that chemical reactions resulted from the combination or reshuffling of atoms. During the first half of the 19th century new elements were discovered at an increasing rate. The most recent discovery of a new element took place in April 1995 with the isolation and identification of element number 110 by German scientists.

World War II research spurred important advances in Inorganic Chemistry, the science of basic elements. The atomic weapon and nuclear power projects intensified studies of uranium and the transuranium elements, the chemistry of fluorine compounds, and the metallurgy of fuel element components such as zirconium. Rare earths, produced by nuclear fission, were separated in pure state by chromatography and were made available for chemical study. Organic Chemistry, branched out as a science of chemicals that contained carbon base. This science grew rapidly during the 20th century, as evidenced by the increase in the number of known organic compounds from approximately 12,000 in 1880 to one million in 1960. Today, this number goes into several millions. Before World War II organic chemistry was based on the coal-tar industry, but after the war petroleum became the major source of organic compounds. Petrochemicals were produced in thousand-ton lots for the plastics, fiber, and solvent industries. The first sulfa drug, prontosil, became available in 1932. The antibiotic penicillin was made in the laboratory in 1957.

Physical Chemistry, a discipline on the border between physics and chemistry, is concerned with the macroproperties of chemical substances and the changes they undergo when subjected to pressure, temperature, light, and electric and magnetic forces. It also investigates changes produced by dissolution in a solvent or chemical reactivity. During the second third of the 20th century, Chemical Physics was identified as a new discipline. Chemical physics differs from physical chemistry in that it deals with the microscopic properties of different chemical substances (spectra, X-ray structures, microwave spectroscopy, and the study of magnetic resonance), and interprets the results in terms of atomic and molecular theories. Such interpretations are based on quantum mechanics, quantum chemistry, and statistical mechanics.

Analytical Chemistry, the science of analyzing chemicals took a separate discipline during the last half of the 20th century when instrumental methods replaced the standard gravimetric and volumetric procedures. Instruction in these classical analytical techniques occupies a very small part of today's chemical curriculum in the West as it is gradually replaced by highly technical analytical technologies including use of lasers to study rapid chemical reactions. Since investigation of molecules and atoms that make up the bulk of biological investigations, the science of Biological Chemistry was born a quarter of a century ago; Biochemistry, the science of molecules that make up our body is an essential component of medical curricula. We learn in biochemistry how chemicals convert to energy and how energy is stored as chemicals.

Since all sciences require study of interaction of matter, chemistry precedes all scientific disciplines. Advances in other sciences such as electronics, physics and computers has provided this highly sophisticated branch of science, complex apparatuses for experimental work and a highly refined theoretical approach in the interpretation of results. Chemistry is part of just about all sciences whether it is manufacturing of computer chips, fabrication of Kevlar sheets to mold space probes or surgical implants and prosthetics.

Chemistry has also been a favorite subject of study in our part of the world. The Indian subcontinent has produced several world-renowned chemists. The famous Raman Spectra to study chemicals yielded a Nobel for Dr. Raman of India; Dr. Salimuzzaman Siddiqui who died last year stood clearly in the ranks of these scientists. Thousands of years of alchemy on this subcontinent has yielded many new discoveries, particularly the drugs from indigenous sources since the Ayurvedic and the Greek systems of medicine had taken roots here hundreds of years before the West discovered these drugs. We still call pharmacists, chemists as a carry over of our belief in chemistry.

The teaching of chemistry in Pakistan has, unfortunately, not kept pace with the advances in science. Much of the curricula is archaic and misses out the molecular approach now used worldwide, i.e., learning about molecules from inside out instead of peeling-off molecules from outside in, an approach that has run-out its utility. In a style that can be called classic, the teaching of chemistry in Pakistan begins with rote memorization of chemical structures that takes so much time that there is little opportunity left to study molecular interactions. The current curricula of chemistry at the B.Sc. and even at the M.Sc. level does not inculcate understanding of basic chemical theory as a high school graduate of the West would have today. We spend an inordinate amount of time in teaching archaic techniques of chemistry such as the qualitative and quantitative wet and dry tests, which are nice to know but have little practical use as the modern analytical techniques of high pressure liquid chromatography, laser spectroscopy, fourier-transform infra red imaging have replaced many of these tests. The problem lies in training the teachers who are mostly products of the old-mill; the mill continues to churn out outdated stuff. Unavailability of sophisticated instrumentation at the universities makes it difficult for both teachers and students to appreciate the utility of instrumentation. The textbooks used are at least a couple of decade obsolete and no effort is made to upgrade them. Even though this problem of curricular obsolescence exists for all basic science disciplines in Pakistan, the impact is quickly and deeply felt in the chemical sciences where changes are taking place within months rather than years.

Chemists, whether they are busy refining petroleum, identifying, analyzing and synthesizing new drugs, or exploring conversion of nutrients to energy, are perhaps the most important part of industrial production and research teams. Creating new uses of matter, chemists are indispensable in improving our quality of life. Unfortunately, we are producing too many chemists than can be employed as chemists; the positions that can really use good chemists go begging since our chemistry graduates are not properly trained in the use of modern techniques. We need to upgrade our teaching facilities to equip the graduates with the tools they need to work in varied environments. And for chemists there should always be opportunities to practice their profession.

[23 Setpember 1995]