Section 1-2 Teaching Outline

Section 1-3 Teaching Outline

Book K

Anticipatory Set
Do Discovery Activity p 29K

Items used: Two boxes with toy cars in them and pass around, Don’t take too much time

Procedure: Have them observe and list their observations or write them on the board.
Discuss indirect evidence and examples such as crimes (OJ), smoking, kisses (lipstick) etc.
Assign Reading

Go over reading hints p.29
Give out the outline 1-3. Discuss objectives
Have them read p. 29 Discuss

Activity: Pass out photo quality print, then pass out draft print and magnifying glasses.
Ask them how an entire picture can be made up of tiny parts. Tell them that matter and ourselves are formed the same way out of very tiny parts. So small that we have to use indirect evidence to describe them because we can’t see them.

Objectives:

Explain how atoms are the particles that make up all matter.
Describe Dalton’s theory of atoms.
Identify chemical bonds as holding atoms together in molecules.

The Reading Presentation:

Atoms: what If you took a piece of aluminum foil and tore it up

Or what if you took cube of salt and chopped it up to the smallest parts? What would you eventually have. Molecules, Atom, pieces of atoms, energy. This question has been debated for more than 2000 years.

Today scientists agree that atoms are the smallest distinct pieces of matter from which all matter is made. (Energy, Particles are not distinct)

Democritus: was a greek philosopher who first wrote about this idea in 440BC. There is a point where matter can no longer be divided. He called these pieces the uncuttable or in Greek atomos.

John Dalton (1766-1844) Notice the huge time gap from 440BC. In 1802 came upwith a new theory based on experiments he conducted (a scientist not a philosopher)

Describe his work with gases and ratios. Give the water example.

This is an example of indirect evidence. He described something he couldn’t see

(2 H + 1 O = 1 H2O) by volume (80g O + 10g H = 90g H2O) by mass

His Conclusions:

Atoms cannot be broken into smaller pieces.
In any pure element the atoms are exactly alike
Atoms of two or more elements can combine to form compounds.
Atoms of each element have a unique mass. (this is why the same volume of similar elements have different masses)
The masses of the elements in a compound are always in a constant ratio.

While his theory was very important in our ideas about the atom, he inspired new research that found some of his ideas were wrong. Atoms and Molecules: Just as our spots of red yellow and blue can be combined to make almost any color, the atoms can be arranged to make molecules that form all matter.

What makes a molecule different than a mixture of atoms is that the atoms are joined together and cannot be easliy seperated. This joining is done with chemical bonds similar to the attraction of magnets, but often much stronger.

Look at p 32K at How small is small, to get an idea of the size of atoms and molecules.

See p 33 K (figure 15) Our best image of an atom

Models, mental images or descriptions of how things work that we cannot really see.

Assignment:

Do the in your journal activity and complete your worksheet