Argon is an inert gas in group VIII A of the periodic table with atomic number 18, an atomic weight of 39.948, and a density of 1.40 Mg/m 3. In the solid state it forms an fcc crystal with a melting ...

Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came ... Rutherford deduced that the atom must have nearly all its mass, and positive charge, in a central nucleus ...

However, there was still a difference between the atomic number of the atom and the atomic mass. Bohr and other scientists knew that there also had to be a neutral particle the same size as a ...

Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came ... Rutherford deduced that the atom must have nearly all its mass, and positive charge, in a central nucleus ...