THE STRUCTURE OF AN ATOM

THE STRUCTURE OF AN ATOM

1. Matter is anything that occupies space and has mass

2. The Atomic Structure

   • John Dalton
     • Proposed the Atomic Model
   • J.J Thomson
     • Discovered Electron,a -ve particle
   • Ernest Rutherford
     • Proton,+ve & Nucleus in centre
   • Niels Bohr
     • Electrons move in shell and the orbit
   • James Chadwick
     • Proved existence of neutrons,nucleus contain proton and electron& nucleus is 1/2 mass of atom

3. Isotopes

   • Cobalt-60 for Cancer
   • Carbon-14 for age of fossils
   • Sodium-24 for oil leaks

4. Diffusion occurs when the particles of a substance move between the particles of another substance from a region of high concentration to low concentration