How did democtitis define atom?

Democritus, theorized that atoms were specific to the material which they composed. In addition, Democritus believed that the atoms differed in size and shape, were in constant motion in a void, collided with each other; and during these collisions, could rebound or stick together.

Explanation:

One of the main atomic theorists was Democritus, a Greek philosopher who lived in the fifth century BC. Democritus realized that if a stone was partitioned fifty-fifty, the two parts would have indistinguishable properties from the whole. Therefore, he contemplated that if the stone were to be constantly cut into littler and littler pieces at that point; sooner or later, there would be a piece that would be so little as to be inseparable. He called these small pieces of matter as "atomos", the Greek word for inseparable.   Democritus estimated that atoms were explicit to the material which they made. Also, Democritus accepted that the particles varied in size, were an inconsistent shape, crashed into one another; and during these impacts, could bounce back or stay together. Hence, changes in the matter were a consequence of separations or mixes of the atoms as they moved all through the void.

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