Text 14 В - раздел Образование, Part One THE PREDICATE Прочтите Текст Про Себя (Контрольное Время Чтения — 3 Минуты). The Atomic The...
Прочтите текст про себя (контрольное время чтения — 3 минуты). The Atomic Theory of Democritus and Dalton
The Greek philosopher Democritus (about 460-370 B.C.) who had adopted some of his ideas from earlier philosophers, stated that the Universe is composed of void (vacuum) and atoms. The atoms were considered to be everlasting and indivisible — absolutely small, so small that their size could not be diminished. The atoms of different substances, such as water and iron, were considered by him to be fundamentally the same, but to differ in some superficial way; atoms of water, being smooth and round, could roll over one another, whereas atoms of iron, being rough and jagged, would cling together to form a solid body. The atomic theory of Democritus
was pure speculation, and was much too general to be useful. Dalton's atomic theory, however, was a hypothesis that explained many facts in a simple and reasonable way.
Dalton stated the hypothesis that elements consist of atoms, all of the atoms of one clement being identical9, and that compounds result from the combination of atoms of two or more elements, each in definite number. In tliis way, he could give a simple explanation of the law of conservation of mass and of the law of constant proportions.
