Unit 1• Atomic Structure• Atomic Mass and Mole Calculations• Ionic Bonding• Metallic Bonding• Covalent Bonding• Organic Chemistry• Polymers
Kinetic Theory of Matter…• All matter is made up of particles• Different substances have different
sized particles• Particles are always moving - move
faster at higher temperatures• Particles are held together by bonds that vary in strength
States o MatterSolids Liquids Gases
Space between particles
Very small Very small Large
Bond between particles
Strong (rigid structure)
Strong Very weak
Movement of particles
Vibrate in a fixed position
Roll over each other
Move freely
States of Matter
• Substances change state when energy or heat is added to them
• Heat gives the particles more kinetic energy causing them to expand
• *copy the diagram
Changes in states of matter
• Melting Point• Freezing Point• Boiling Point • Condensation Point
Write a definition for the following words:
Most atoms are combined with others in nature.
PHASE CHANGECH3CH2OH (l) CH3CH2OH (g)
CHEMICAL CHANGE CH3CH2OH + 3 O2 2 CO2 + 3 H2O
Pure Substances and Mixtures
• Consist of only 1 type of atom
O O OO O
OO
O
O OOO
O
Oxygen Atom
Element
Example: oxygen
Elements-
• A group of two or more atoms linked together by a covalent bond
O O
Examples: oxygen water
O
HH
Molecule-
PRACTISE
Each shape below represents an atom of a particular element. a) State whether each is a representation of a group of atoms or a group of molecules.b) State whether the diagram represents an element, a compound, or a mixture.
Practise
In a physical change, the substance involved remains the same substance, even though it may change state or form.
In a chemical change, the original substance is changed into one or more different substances that have different properties.
Physical vs. Chemical Changes
3
The following are clues that a chemical change has happened:
• Heat or light is given off
• Bubbles of gas are formed
• A new colour appears
• The change is difficult to reverse
• A solid material (called a precipitate) forms in a liquid