The atomic theory of matter
The vital breakthrough that allowed chemistry to become the central science was the demonstration of the atomic nature of matter. In about 1800 John Dalton realized that all matter is composed of relatively few elements. He postulated that these elements combine together in accordance with their valency to make up discrete molecules. (Thus, water, H20, is formed by the combination of two hydrogen atoms with one oxygen atom.) Antoine Lavoisier proved that burning is simply the chemical combination of the combustible material with the oxygen of the air. In the early nineteenth century, Friedrich Wohler synthesized urea from inorganic materials and demonstrated that there is no difference in principle between inanimate substances and those of living matter.
The atomic theory allows us to treat all the properties of matter in terms of the molecules that make it up. This has enabled the development of chemistry (and physics) to progress rapidly. An explanation in terms of molecular structure allows scientists to carry out rational experiments to test the explanations. Furthermore, correct explanations of significant and desired properties lead to the possibility of predicting improvements to those properties by molecular modification. This, in turn, then allows additional experiments to produce materials with such improved properties.
This chain of events is the basis of all applied research, and the chief reason why living standards have so improved that in the developed nations the good life should now be possible for everyone.
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The atomic theory allows us to treat all the properties of matter in terms of the molecules that make it up. This has enabled the development of chemistry (and physics) to progress rapidly. An explanation in terms of molecular structure allows scientists to carry out rational experiments to test the explanations. Further-more, correct explanations of significant and desired properties lead to the possibility of predicting improvements to those properties by molecular modification. This, in turn, then allows additional experiments to produce materials with such improved properties.
This chain of events is the basis of all applied research, and the chief reason why living standards have so improved that in the developed nations the good life should now be possible for everyone.
Chemistry and the biological sciences
In the last 50 years, chemistry has become the language of the biological sciences and the basis of many of its most important experimental theories and methods. For example, reproduction is central to the concept of living matter. Since James Watson and Francis Crick broke the genetic code in the late 1950's, we understand in molecular terms how information is passed from one generation to another. Genes are made up of nucleic acids; nucleic acids allow the synthesis of proteins in living organisms; and proteins are the universal catalysts for the chemical processes that make up life.
The science of molecular geneticsliterally genetics explained by chemistryhas already had great influence on world food production through the development of new improved strains of crop plants and farm animals. And much more progress lies just ahead.
