Topic: Development of Atomic Structure
(text pg 106 -111)
Hoberman sphere
(represents path of electrons around nucleus of atom) a marble placed on second base of the Houston Astrodome would be the approximate
ratio of size of nucleus: atom.
Democritus
(Greek) atomos = indivisible [bowling ball model of atom]
atom had NO protons, neutrons, electrons and was solid and indestructible
Dalton (~1803)
Text 5.1
Dalton Model of the Atom (pg 107 - 108) used
chemical symbols to show what was occurring during chemical reaction
Experimental (empirical) evidence for existence of atoms (discontinuous theory of matter)
law of definite composition (Proust) law of multiple proportions law of conservation of mass
Dalton's Postulates of Atomic Theory
Story: Daltonism = colorblindness
(Will start Cathode Ray Tube next lesson)
Cathode Ray Tube (CRT) William Crookes - great-grandfather of television & brother to
fluorescent light bulb
Demonstration: excitation of
cathode rays using a Tesla coil.
Student volunteer to light fluorescent tube light holding on to Tesla coil.
J.J. Thomson - discovered that cathode rays were deflected by a magnetic field
or electric field and realized atoms contained negatively charged particles
(electrons) Text 5.2Thomson Model of the Atom (pg 108)
by Corwin
pg 106-108
Section
5.1 DALTON MODEL OF THE ATOM (pg 107-108) Objective: To describe the Dalton model of the
atom.
Section 5.2 THOMSON MODEL OF THE ATOM (pg 108) Objective: To describe the Thomson plum-pudding
model of the atom.
Objective: To state the relative charge on an electron and a proton.
Notice the deflection of the cathode rays by the magnet.
The gray color are electrons being excited. This is the grandfather of a black & white television.