History of the Atomic Model

1. History of the Atomic Model • Democritus (400 BC)

4. History of the Atomic Model • Democritus (400 BC) • Reasoned that matter was composed of a few indivisible units that combine to make everything around us.

5. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800)

9. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • Conducted experiments that showed small units of matter (atoms) combine in specific ways.

10. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897)

13. CRT animation

21. Plumb pudding model

24. Dr. Cox on Thompson

25. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Squeezed electrons out of atoms demonstrating that atoms are made of smaller particles. Thompson is responsible for the plumb pudding (chocolate chip cookie) model.

26. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Ernest Rutherford (1898)

33. How it works Dr. Cox on Rutherford

37. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Ernest Rutherford (1898) • Demonstrated that atoms contain small heavy positively charged centers. We call that center the nucleus.

38. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Ernest Rutherford (1898) • Niels Bohr

44. Bohr model

45. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Ernest Rutherford (1898) • Niels Bohr • Demonstrated that electrons exist in specific energy levels. As electrons drop from high to low orbitals only specific colors of light are released.

46. History of the Atomic Model • Democritus (400 BC) • John Dalton (1800) • J.J. Thompson (1897) • Ernest Rutherford (1898) • Niels Bohr (1915) • Erwin Schrodinger and Werner Heisenburg (1926)