PARTICULATE VIEW OF MATTER

How big is an atom???

• Write down your answer!

• Let’s see

• Go to Baydar’s schoolwires and click on Chem Comm Sites

• How big is an atom?

MATTER

• Matter- anything that occupies space and has mass; composed of one or more elements

What’s an Element vs. an Atom?

• Atom- building block of all matter

• Element-matter that is made up of only 1 kind of atom

The Element Song

• http://www.youtube.com/watch?v=zGM-wSKFBpo

ELEMENTS

ATOMS

• Made up of subatomic particles

• Proton- positive charge, in nucleus• Electron- negative charge, energy level• Neutron- no charge, nucleus

ATOMS

JOKE- Don’t Have to write this.• A NEUTRON walks into a diner and sits down to order a

meal.• When the waitress brings the food over the neutron says

“Can you bring the check? I am in a hurry!”• The waitress replies, “Don’t worry about it, there is NO

CHARGE for you.”

COMPOUNDS

• Compounds- two or more elements that are chemically combined

• Represented by Chemical formulas

• Example: H20

• NaCl

COMPOUNDS

• Properties of compounds may differ greatly from the elements that make them up

Concept Check!

How are elements and compounds different?

Molecules• Smallest unit of a particular substance• Held together by molecular bonds

Chemical Equations• Chemical formulas are like

words in an overall sentence, the chemical equation

• Reactants on left Products on right

• 2H2 + O2 2H2O

• H2 and O2 are diatomic molecules

Name the Element for each symbol• 1. P• 2. Ni• 3. Cu• 4. Br• 5. K• 6. Na• 7. Fe

Name the elements, and give the number of atoms of each element

• 1. H202

• 2. CaCl2

• 3. NaHCO3

• 4. H2SO4

Think, Pair, Share- Do Now

• Write a chemical formula for nitrous oxide (laughing gas) that is made up of two atoms of nitrogen and one atom of oxygen.

The Electrical Nature of Matter

How do atoms make bonds??• Opposite charges attract

• Like charges repel

• Protons and electrons are responsible for bonding between atoms

Ions• Ionic Compounds- Substances

composed of positive and negative ions

• Anion- Negatively charged ion (electron is gained)• Ex: Cl-

• Cation- Positively charged ion (electron is lost)• Ex: Na+

JOKE- Don’t have to write this.

• Two atoms walk down the street and collide.• One atom says to the other, “Are you okay?”• The second atom replies, “I think I lost an electron.”

• The first atom says, “Are you sure?”• The second one says, “Yeah, I’m POSITIVE!”

Real World Use of IONS• Lithium Ion Batteries

• Li+ Ions carry current from negative to positive electrode

Common Ions