The questions in this quiz are suitable for GCSE chemistry students studying early ideas about atoms, the structure of the atom, atomic number and mass number. If you struggled with the quiz ...

Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came from a very strange experience. Everyone at that time imagined the atom as a "plum pudding." That is ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

Proceedings of the American Academy of Arts and Sciences, Vol. 45, No. 5 (Jan., 1910), pp. 137-158 (22 pages) ...