super model
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Super Model. How are protons and electrons arranged in atoms?. Notebook. Super Model, Part 1 How are electrons and protons arranged in an atom? Put it in your TOC. Page 162. Different spectra caused by differences between atoms Questions we’re asking: HOW are they different? - PowerPoint PPT PresentationTRANSCRIPT
Page 162 Different spectra caused by differences
between atoms
Questions we’re asking: HOW are they different? How does the structure of an atom vary
from element to element?
Models What does a model do?
What does it allow us to do that we normally wouldn’t do?
http://www.youtube.com/watch?v=xqNSQ3OQMGI
Page 167 – What is a Model? Physical Model
An object on a different scale Example?
Conceptual model Describes a system, not a thing Example?
Blind Drawing Activity One person come up to the board
Feel an object in their hands, EYES CLOSED
Have 20 seconds to draw it on the board
You are modeling using evidence…
Process and Procedure #1: Read 164-165 INSTEAD of #2: Explain Rutherford’s experiment by using
a sentence for each of these words. Show how it is related to the reading/experiment.
Use these words: Gold foil, alpha particles, nucleus, empty
space, rebound, target, model, protons, electrons, positive, negative
Web stuff http://
www.mhhe.com/physsci/chemistry/essentialchemistry/flash/ruther14.swf
Stop and Think, p. 169 Let’s just discuss #2
Good discussion looks like what? Respectful Quiet when it’s not your turn Creative
History of the Atom
The modern model of the atom has evolved over a long period of time through the work of many scientists Democritus ▪ matter is made up of particles called atoms
Dalton ▪ atoms of the same element are alike ▪ solid indivisible spheres
Thomson ▪ cathode ray tube ▪ discovers electrons
▪ plum pudding model
History of the Atom
Rutherford Gold foil
experiment ▪ discovers a
massive (heavy) positively (+) charged nucleus
▪ most of the atoms volume is empty space
▪ nuclear model
History of the Atom
Continued Bohr ▪ Hydrogen emission spectra▪ electron energy is quantized – electrons can only
have certain orbits with certain radii▪ planetary model
Schrödinger▪ Aided by many famous scientists (De Broglie,
Heisenberg, etc…)▪ Wave-mechanical or electron cloud or quantum-
mechanical model (very complex)
Question:
Subatomic particles can usually pass undeflected through an atom because the volume of an atom is composed of
(1) an uncharged nucleus(2) largely empty space(3) neutrons(4) protons
Question:
One model of the atom states that atoms are tiny particles composed of a uniform mixture of positive and negative charges. Scientists conducted an experiment where alpha particles were aimed at a thin layer of gold atoms. Most of the alpha particles passed directly through the gold atoms. A few alpha particles were deflected from their straight-line paths. An illustration of the experiment is shown below.