Subatomic ParticlesElectrons, Protons and Neutrons and Their Electrical Charge

MATTER

• All objects contain matter• All matter contains tiny particles in constant

motion• All matter is made from different proportions of

a small number of the basic building blocks….Elements

• WHAT IS AN ELEMENT?• A pure substance that cannot be broken into a

simpler form

ATOMS:

• Atoms are the smallest particles that make up matter• Atoms are the smallest part of an element that

retains the properties of that element

What is a Compound?A substance that contains 2 or more different elements joined together by chemical bonds

ATOMIC THEORY

• Dalton’s Theory from 18081. Matter is composed of tiny, invisible,

indestructible particles called atoms2. An element is composed entirely of one

type of atom. The properties of all atoms of one particular element are identical.

3. A compound contains atoms of 2 or more different elements.

4. Atoms do not change their identities in chemical reactions, they are just rearranged.

EXCEPTIONS TO DALTON’S THEORY

1. We now know that atoms are not indivisible, but are made of smaller particles.

2. Atoms are not indestructible, but can be split.

3. Not all of the atoms of an element are exactly identical.

Subatomic Particles

• The Atom is comprised of 3 subatomic particles• These particles are known as the…• Proton (+)• Neutron (+/-)• Electron (-)

Subatomic ParticlesThere are 3 subatomic particles that make up an

atom…1. The Proton: A positively charged particle that resides in the nucleus.2. The Neutron: A neutral particle that resides in the nucleus along with the proton, and holds the nucleus together3. The Electron: A negatively charged particle that circles the central part of the atom in Orbital RingsThe charges of the proton and electron are equal and opposite

Mass and Volume of an Atom

The protons and neutrons within the nucleus are responsible for giving the atom its mass

• The electrons have little to no mass

The distance between the electrons and the nucleus is what gives the atom its volume

Atomic Number/Atomic Mass• The number of protons in an atom’s nucleus

give it its atomic number.

• The mass of the protons + the mass of the neutrons are what give an atom its atomic mass

• These are numbers that help identify elements on the Periodic Table of Elements

Element Analysis from Periodic Table

PERIODIC TABLE

Groups or Families

Periods

Electricity

STATIC ELECTRICITY

A charge is a fundamental property due to subatomic particles

Static electricity is electricity that is created and remains stationary

It is a charge that is created by friction or the rubbing of surfaces

Van DeGraaff Generator

WHAT IT CAN DO HOW IT WORKS

STATIC CHARGES

• Objects can become charged• Protons are bound to the nucleus, but

electrons can easily be stripped from an object• Objects receiving electrons becomes

negatively charged• Objects losing electrons become

positively charged

DEMONSTRATION• Static Demonstration

• Another Static Demonstration

•When you bring a negatively charged item near a neutral object, you get a static discharge.

• The spark and snap is the ELECTRONS jumping creating a glow

FIELDS AND ATTRACTIVE FORCES

• A FIELD is how the force of electricity, light or gravity gets from one place to another

• All interaction between matter and energy will proceed because of the fields

•We are experiencing the fields created by an object NOT the object itself

ATTRACTIVE FORCE (newtons)

ELECTRIC FIELDS:

• Fields are indicated by drawing “FIELD LINES”

• For electric fields, the field lines are moving away from a + and towards a _

STRENGTH OF A FIELD

INVERSE SQUARE LAW

• The strength of a field will decrease as the distance between objects increases.• The relationship is negative and is

calculated as the inverse square of the distance.• Example: If you increase the distance/double

the distance between you and a light source, you decrease the field strength to ¼ of its original strength

INVERSE SQUARE LAW: