What were the conclusions that were drawn from Rutherford's scattering experiment?
Rutherford's scattering experiment using gold foil - Alpha particles fired at gold and most particles passed through and a small number reflected back.
This meant that atoms had a small positive area surrounded by a cloud of electrons.
Who discovered the neutrons?
Chadwick
Dalton - proposed that atoms were solid spheres of matter that could not be divided
Thompson - discovered the electron, atoms weren't solid, new model created known as the plum pudding model.
Bohr - theorised that electrons exist in shells or orbits of fixed energies, electrons can move shells when energy is emitted or absorbed, later developed to include sub shells.
Chadwick - discovered neutrons, nucleus of the atoms defined as protons and neutrons
Mass number - the total number of protons and neutrons in a nucleus
Element symbol - identifies the element, which all atoms have equal numbers of protons
Atomic number - the total number protons in an atom
