1. Atomic Models
Chemistry

2. Why is Lego™ the most ingenious toy in the world?
Excerpt from Sophie’s World©
By Jostein Gaarder

3. Models Empedocles, ~450 BC Democritus, 400 BC John Dalton, ~1800
Thomson Model, 1904
Nagaoka / Rutherford Model, 1911
Robert Milliken
Bohr Model, 1913
Schrodinger’s Model, 1925
Louis DeBroglie
Lise Meitner
James Chadwick
Linus Pauling
Peter Higgs/Francois Englert

4. Why?

5. Empedocles, ~450 BC Earth, Air, Fire, Water
Love and Strife changes the elements
Love unites elements
Strife drives elements apart
Aristotle called him “The Father of Rhetoric”

6. Democritus (~400 BC) The Happy Philosopher “Atomos”-cannot be divided
“The Void”
Nothing exists except atoms and empty space; everything else is opinion.

7. Democritus (~400 BC)
Nothing exists except atoms and empty space; everything else is opinion.

8. John Dalton 1766 – 1844 English, Born a Quaker and the son of a weaver
Did research on color blindness, atomic theory, gasses, atomic weights, meteorology
Proposed a version of the periodic table
Proposed Dalton’s Atomic Theory

9. John Dalton
Proposed a version of the periodic table

10. Dalton’s Atomic Theory
Elements are made of tiny particles called atoms
All atoms of a given element are identical
The atoms of a given element are different from those of any other element
Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers and types of atoms (The Law of Constant Composition).
Atoms are indivisible in chemical processes. That is, atoms are not created or destroyed in chemical reactions. A chemical reaction simply changes the way atoms are grouped together.

11. - 1897

12. - 1897

14. Hantaro Nagaoka 1904 Japanese physicist from Nagasaki
Suggested that an atom has a central nucleus to which electrons orbit like the rings of saturn.
This is the “Typical” model initially used to describe the atom

15. Ernest Rutherford
Ernest Rutherford's family emigrated from England to New Zealand before he was born. They ran a successful farm near Nelson, where Ernest was born. One of 12 children, he liked the hard work and open air of farming, but was a good student and won a university scholarship. After college, he won another scholarship to study at Cambridge University in England -- a turning point in his life. There he met J.J. Thomson (who would soon discover the electron), and Thomson encouraged him to study recently- discovered x-rays.

16. Rutherford reasoned that all of the atoms positively charged particles were contained in the nucleus. The negatively charged electrons were scattered outside the nucleus around the atoms edge.

18. Robert Millikan 1910 (1913)
Determined the charge and energy of the electron. + -

19. Niels Bohr
Model of the atomic structure,1913

21. Louis De Broglie 1924 French physicist
Proposed that electrons have some properties of waves based on work by Einstein and Planck (Wave-Particle
duality duality of light).

22. Erwin Schrodinger 1925 The Founder of Quantum Wave Mechanics
Determined an equation to determine the location of an electron based upon probability
Credited for development of the Quantum Mechanical Model of the atom

23. James Chadwick 1932
By repeating the experiments of Jean-Frédéric Joliot and Irène Curie, found evidence of a neutrally-charged particle he called a neutron.
Joliot and Curie bombarded boron, aluminum, and magnesium with alpha particles to make radioisotopes.

24. Lise Meitner 1939
Co-Discoverer of nuclear fission, proving that the atom’s nucleus may be “opened”.
After facing multiple examples of sexism, she was not named with Otto Hahn when he received the Nobel Prize in 1944.

25. Linus Pauling 1951
Using quantum mechanics and analytical techniques such as X-Ray crystallography, Pauling worked on clarifying the nature of the chemical bond.
Orbital hybridization and valence theory
Won 2nd Nobel for anti-war efforts

26. Peter Higgs/Francois Englert

29. Models Empedocles, ~450 BC Democritus, 400 BC John Dalton, ~1800
Thomson Model, 1904
Nagaoka / Rutherford Model, 1911
Robert Milliken
Bohr Model, 1913
Schrodinger’s Model, 1925