The Atom

• Atomic Clock• Atom Bomb• Atom Ant

What Do You Think?

• Draw a diagram of what you think an atom looks like.

• Are atoms mostly – Empty space– Stuff– Equal parts of each

Challenge Question

• Atoms are mostly …

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Connection

• If an atom had 11 protons, how many electrons does it have?

How do you know?

VocabularyDefine in words, diagrams or both

• Proton• Neutron• Electron• Nucleus• Electron cloud• Charge• Element• atom

Check Quizlet – I have made this set for

you.

Resources (places to look for information)

• Bill Nye – https://www.youtube.com/watch?v=CnjxrFNie5I

• Holt Physical Science Text, pages 288-289• Sciencesaurus Text, pages 255-257• Chem4Kids-

http://www.chem4kids.com/files/atom_intro.html

• The Atom PowerPoint – (see Science Website)

Objective Notes

Describe what an atom is

Describe an element

Describe the subatomic particles that make up atoms

Describe how atoms are put together

Particle Location Charge Mass Other

Parts of an AtomNotes

First off, what is an atom?

• Atoms are the smallest parts to which an element can be divided yet still be that element.

• Atoms are the building blocks of all matter.

Describe an element

• A substance made up of only one kind of atom

How small is an atom?

• An atom is so small that a penny contains about 2 x 1022 or 20,000,000,000,000,000,000,000 atoms!!!

But there’s more…

• Atoms consist of even smaller particles. These include:–Protons–Neutrons– Electrons

The Nucleus

• The center of an atom• Small, dense (packed tightly)• Contains protons and neutrons: most

of the atom’s mass• So dense, if it were the size of a grape,

it would weigh over 9 million tons!

Protons

• Located in the nucleus

• Positive charge (+)• Mass of 1 atomic

mass unit (amu)

protons = positive

Neutrons

• Located in the nucleus

• Have no charge - neutral

• Mass of 1 amu

neutrons = neutral

Electrons

• Found outside of the nucleus in electron clouds – (think of rings around a target)

• Negatively charged (-)• Mass of almost zero• Number of electrons equals the numbers of

protons to cancel out the charges – (think of -1+1=0)

electrons = negative

How Atoms Are Put Together

The protons and neutrons make up the center or nucleus.

Objective Notes

Describe what an atom is

Atoms are the smallest parts to which an elements can be divided yet still be that element.

Describe an element

A substance made up of only one kind of atom

Describe the subatomic particles that make up atoms

Describe how atoms are put together

Protons and neutrons packed tightly in the small dense nucleus (center).Electrons (with nearly no mass) zip around the nucleus in a region called the electron cloud.The electron cloud region of the atom is mostly empty space because it encompasses such a large area of the atom – atoms are mostly empty space

Particle Location Charge Mass Other

Proton nucleus + 1 amu

Neutron nucleus none 1 amu

electron Electron cloud

- Almost zero Number of electrons equals the numbers of protons to cancel out the charges

(think of 1+1=0)