Matter &The Atom

Matter

The term matter describes all of the physical substances around us: your table, your body, a pencil, water, and

so forth

Matter

Anything that has mass and takes up space (has volume)

Made up of different kinds of atoms

Matter

Includes all things that can be seen, tasted, smelled, or touched

Does not include heat, sound, or light

Matter is made of atoms

Models

Models are often used for things that are too small or too

large to be observed or that are too difficult to be understood easily

Models

In the case of atoms, scientists use large models to explain something that is very small

Models of the atom were used to explain data or facts that were gathered experimentally.

So, these models are also theories

Modern Model of the AtomThe electron cloud

Sometimes called the wave modelSpherical cloud of varying density Varying density shows where an electron is more or less likely to be

Atomic Structure

Nucleus – Protons

– Neutrons

Electrons

Atomic Structure

Protons

-Much larger and heavier than electrons

– positive charge (+)– Located in the nucleus of the atom 

Atomic Structure

Electrons

Tiny, very light particles

Have a negative electrical charge (-)

Move around the outside of the nucleus

Atomic Structure

Neutrons

Large and heavy like protons

Neutrons have no electrical charge

Located in the nucleus of the atom 

Draw the following picture on your output p.22.

Atomic Structure

Let’s look at the periodic table and determine what each square tells us!

Let’s Practice!- Output p.23Please copy the table into CB

Element #Protons #Neutrons #Electrons

Oxygen

Calcium

Aluminum

Tungsten

Nickel

Let’s Practice!- Output p.23Please copy the table into CB

Element #Protons #Neutrons #Electrons

Oxygen 8 16 – 8 = 8 8

Calcium 20 20 20

Aluminum 13 27-13=14 13

Tungsten 74 184-74=110 74

Nickel 28 59-28=31 28

Describing Atoms

# of protons

+ # of neutrons

Atomic mass number

Describing Atoms

Atomic Weight - average mass of the naturally occurring isotopes of an element .