Chemistry
Starring ...Oxygen and Magnesium.... OMg !

Changes of State A change of state involves moving to a melting point, or a feeling point. Substances change between states (Solids, Liquids, Gas) | Particle Theory of Matter 1. All Matter is composed of very tiny objects called particles. 2. All particles have spaces between them. 3. Particles in matter are ALWAYS in motion. 4. Particles in a substance attract each other. | Matter has many forms Matter is anything that has mass and volume. Matter can be in a single state, or be a combination of sates. Styrofoam is a solid plastic with trapped air (gas). |
Changes of State
Substances change between states (Solids, Liquids, Gas)
Particle Theory of Matter
2. All particles have spaces between them.
3. Particles in matter are ALWAYS in motion.
4. Particles in a substance attract each other.
Classification of Matter
Element = Pure substance that cannot be broken down into any simpler substance by
chemical means. (Found on the PERIODIC TABLE)
Compound = Pure substance that is made from 2 or more elements that are chemically
combined. (Carbon Dioxide, Water, Carbon Monoxide, Salt NaCl)
Heterogeneous Mixture = Mechanical Mixture or Suspension (Cereal, Stew)Homogeneous Mixture = Solution (Kool-aid, Coffee)
Physical Property
Three physical properties of the beach glass below:
Lusture (shiny) Colour (red, green, blue) Transparency (how see through it is)

Chemical Properties
Chemical properties includes how a substance INTERACTS with other substances.
Eg. Acids, water, heat, combustibility
Physical and Chemical Change
(cutting paper, grating cheese, melting ice, chopping wood)
Chemical Change: a change in matter that results in the formation of a new substance(s).
(cooking an egg, burning wood, metal rusting, copper oxidizing)
Atomic Theory
2. All the atoms of an element are identical in properties such as size and mass.
3. Atoms of different elements have different properties.
4. Atoms of different elements can combine in specific ways to form new substances.
Sub-Atomic Particles
Protons - Positive charge - found in the nucleus
Neutrons - No charge - found in the nucleus
Electrons - Negative charge - found in energy levels surrounding the nucleus

Bohr - Rutherford Diagrams
Ions
Atomic Theory
1. All matter is made of small, indivisible particles called atoms
2. All the atoms of an element are identical in properties such as size and mass
3. Atoms of different elements have different properties.
4. Atoms of different elements can combine in specific was to form new substances.
J.J Thompson

Ernest Rutherford - Gold Foil Experiment
Rutherford conducted an experiment in which he shot positively charged particles at a very thin foil of pure gold. Based on his experiment he discovered the nucleus.
He calculated that the size of the nucleus compared to the rest of the atom was like the size of a single green pea compared to an entire football field!
Niels Bohr - Electron Energy Levels
Bohr studied the properties of electrons in atoms and helped to transform Rutherford's model into one of the models that is used today.
He suggested that electrons surround the nucleus in specific energy levels, called shells.

Elements on the Periodic table
Metals
1. Most of the elements on the periodic table are METALS.
2. Excellent conductors of electricity and heat.
3. Most are shiny and a silver or grey colour.
Non-Metals
1. Grouped together mostly because they do not resemble metals.
2. Not good conductors of electricity/ heat.
Metalloids
1. Have metallic and non-metallic properties.
2. Are generally 'semi-conductors' (conduct some electricity, but not very well)

Families of the Periodic Table

Trends of the Periodic Table
1. Number of valence electrons for each group.
2. Number of electron shells
3. Valence number (+1, +2, +3, +/-4, -3, -2, -1)
4. Reactivity (Group 1 is HIGHLY reactive, Nobel Gases are un-reactive)
Ionic Compounds
Ionic compounds are PURE SUBSTANCES that consist of at least one metal and
one non-metal. When two atoms combine, both atoms change into an ion (they both have full outer shells). - see pictures below


Molecular/ Covalent Compounds (Carbon dioxide, Water, Hydrogen Peroxide)
When non-metals combine, a pure substance is formed called a molecular/covalent compound.
These molecules SHARE electrons so that they can have a complete outer shell.

Naming Ionic Compounds
ex. Sodium and Chlorine (NaCl)
Name the Metal + Name of non-metal + ide = Sodium Chloride
Find the formula For an Ionic Compound
Step 1: Write down the element symbols
Step 2: Write the valence number above both symbols
Step3: "Criss-Cross" the numbers down
Step 4: Reduce or "simplify" if possible
(see example below)
