At the beginning of the nineteenth century, Berzelius was the first scientist who classified elements into two main groups (metals and nonmetals), according to their physical properties, Indeed that was before knowing anything about...
On heating atoms of a pure elements – in gaseous or vapor state – to a high temperature or exposing them to a low pressure in an electrical discharge tube , they emit a...
Long time ago man was asking about the nature of matter and its structure , while the trials done by the scientists to answer this question across different eras , the concept of the...
Matter is composed of atoms , These atoms show the physical and chemical properties of the matter , By the end of the nineteenth century , Scientists had become sure that electrons are from...
