History of the Atom and Atomic Structure.

-1897 JJ Thomson figured out that atoms weren't solid spheres.
-> measurements of charge and mass showed atom must contain electrons.
-> made the plum pudding model where negative electrons were spread through the postive pudding that made up most of the atom.
-1909 Ernest Rutherford, working with Hans Geiger and Ernest Marsden, conducted the gold foil experiment.
-> fired positively charged alpha particles at thin sheets of goild foil.
-> expected the particles to pass straight through from the plum pudding model or only be slightly deflected.
-> some did actually pass through but more than expected deflected and a few more deflected back.
-> rutherford came up with the nuclear atom. Most of the mass of an atom is concentrated by a tiny, positively charged nucleus at the centre…