What is the most important fact in all of science?

Come up with your own suggestion

AtomsAtoms an Heat Lesson 3

Year 11 Physics

Learning IntentionsUnderstand the importance of atoms to science

Describe some of the evidence that matter is made from atoms.

Richard Feynman

“All things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. “

1918 - 1988

Six easy pieces

“Fiction Physics”

“Atoms are things which can never be seen or touched and only exist in our imaginations”

“Have you seen one?”How can, one generation after scientists doubt their existence, atoms be considered the most important fact in all of science?

Ernst Mach1838 - 1916

What is the atomic model?

It is not just that everything is made out of tiny spheres (balls).

There are different types of balls; atoms, molecules and ions.

The balls are moving.

It is called particle theory or kinetic theory

Atoms intro

Why do scientists think they exist?

Example of a allegorical model

First “used” by John Dalton to explain the ratios of products produced in chemical reactions.

As a model it explains and predicts most of material science (chemistry) and tons of physics.

It works!

Any evidence?

It is not possible to “see” atoms. They are smaller than the wavelength of light.

There is other evidence.

1. Brownian motion

2. Gas diffusion

Have you seen one?

Can a crime be prosecuted without witnesses?

Atom images We can now produce images of atoms using scanning tunnelling microscopes (STM)

Using kinetic theorySuccess Criteria…

Use the ideas of kinetic theory to explain Brownian Motion or Gas Diffusion.

Your explanation must

- include diagrams

- describe the macroscopic event and why it is strange

- use the idea of moving invisible microscopic particles

Diffusion in liquids

Watch the video clip

Success Criteria

Explain the results of the experiment.

Use the ideas of kinetic theory

Use diagrams

Diffusion in liquids

Demonstrate your learning – Dear Mr Mach

Write a letter to Ernst Mach

The purpose is to convince him that atoms exist.

They are not just a useful model

Success Criteria

Letter has an introduction

Use examples and evidence

Letter has a conclusion

Uses key words precisely