Presentation is loading. Please wait.

Presentation is loading. Please wait.

Copyright © by Holt, Rinehart and Winston. All rights reserved. Atoms Table of Contents Section 1 Development of the Atomic Theory Section 2 The Atom Chapter.

Similar presentations


Presentation on theme: "Copyright © by Holt, Rinehart and Winston. All rights reserved. Atoms Table of Contents Section 1 Development of the Atomic Theory Section 2 The Atom Chapter."— Presentation transcript:

1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Atoms Table of Contents Section 1 Development of the Atomic Theory Section 2 The Atom Chapter 4

2 Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 1 Development of the Atomic Theory Objectives Describe some of the experiments that led to the current atomic theory. Compare the different models of the atom. Explain how the atomic theory has changed as scientists have discovered new information about the atom. Chapter 4

3 Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 1 Development of the Atomic Theory The Beginning of the Atomic Theory Democritus, a Greek philosopher Around 440 BCE thought that you could have a particle that could not be cut. Called it an atomos. Aristotle, another Greek philosopher, disagreed Basis: What holds the atoms together? Democritus couldn’t answer the question Chapter 4

4 Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 1 Development of the Atomic Theory The Beginning of the Atomic Theory, continued Democritus was right: Matter is made of particles, called atoms. atom is the smallest particle into which an element can be divided and still be the same substance. Chapter 4

5 Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 1 Development of the Atomic Theory Dalton’s Atomic Theory Based on Experiments John Dalton published his atomic theory in His theory stated all substances are made of atoms. Atoms are small particles that cannot be created, divided, or destroyed. Atoms of the same element are exactly alike, and atoms of different elements are different. Atoms join with other atoms to make new substances. Not Quite Correct Chapter 4

6 Copyright © by Holt, Rinehart and Winston. All rights reserved. Definition of an Atom The smallest particle of an element that retains the properties of the element How small? –World population in 2000 was about 6 billion –One penny contains 5 billion times more atoms

7 Copyright © by Holt, Rinehart and Winston. All rights reserved. Can we See Atoms Only with ‘scanning tunneling microscopes Nanotechnolgy manipulates individual atoms to make very small devices –Next generation of computers will have wires one or two atoms wide (smaller, less power, less heat)

8 Copyright © by Holt, Rinehart and Winston. All rights reserved. Pictures

9 Copyright © by Holt, Rinehart and Winston. All rights reserved. Pictures


Download ppt "Copyright © by Holt, Rinehart and Winston. All rights reserved. Atoms Table of Contents Section 1 Development of the Atomic Theory Section 2 The Atom Chapter."

Similar presentations


Ads by Google