The Idea of the Atom
Text 14 A The Idea of the Atom - раздел Образование, Part One THE PREDICATE Many Times During The Coursc Of History Men Believed That The Solid Matter, O...
Many times during the coursc of history men believed that the solid matter, of which the different things in the world arc made, was really continuous matter. They thought that if you could look at the surfacc of a stone with magnificaton unlimited, you would always sec a continuous surfacc, no matter how much you turned up the magnification. They believed that you would not find individual particles like atoms and electrons. They argued that if you had a magic knife by which you could cut the stone into smaller and smaller pieces, you could continue cutting it up indefinitely and could make the pieces as small as you like — a trillion, quadrillion, quintillion times smaller or even infinitely small. But some twenty-five hundred years ago, there lived in Greece a group of men with inquiring minds, who perceived that this argument for continuous matter was not sound. Facing the fact that the world contains so many different kinds of matter— stones, metals, vegetables matter, animal matter, solids and liquids of so many forms — they argued that it was more logical to believe that all these varieties of matter are brought about by coupling together a relatively few kinds of particles, which could not be cut up any further. Because the indivisibility was taken to be the fundamental property of these particles, they gave them the name atom, or a-tom which in Greek means unciittable. It is astonishing that this purely philosophical guess turned to be confirmed so completely two thousand five hundred years later. Of course, today all atoms arc cuttablc into smaller particles, such as the electrons in the outer shells and the fundamental particles in the inside of the nucleus; but the truly fundamental particles of which atoms are made, arc sure to be uncuttable and they arc true building blocks of all matter.
During the period of fourteen years beginning with 1897, it was discovered that atoms are composed of smaller particles. The discovery of the components of atoms and the investigation of the structure of atoms is likely to be one of the most interesting stories in the history of science. Moreover, knowledge about the electronic structure of atoms has made it possible to systematize the facts of chemistry in a striking way, making the subject easier to understand and to remember: it has been discovered that the bonds that hold atoms together in molecules, consist of pairs of electrons held jointly by two atoms. So those ancient Greeks were right in the ultimate sense of the argument.
