1. Understanding the Properties of Compounds
Chapter 6

2. 6.1 Ionic Compound
Where one or more electrons of one atom are transferred to another atom
Linked by ionic bond which is formed by the attraction between oppositely charged ions
Usually composed of a metal and one or more non metals

3. Properties of Ionic Compounds
Mostly exist in crystal lattice arrangement
(regular repeating pattern of ions)
Often solid with high melting points
Often soluble in water
Often conduct electricity when melted

4. Examples 1. Sodium Chloride (NaCl)
Also known as salt used to flavour food
Also used to de-ice roads in winter (lowers the freezing point of water)
2. Sodium Fluoride (NaF)
Found in toothpaste used to strengthen tooth enamel

5. Examples 3. Calcium Carbonate (CaCO3) Also known as chalk
4. Magnesium Carbonate (MgCO3)
Also known as scum (hard, white scales on bath tub, water kettle)

6. How Ions Dissolve
Water separates the negative and positive ions from each other and break the ionic bonds
Each ion is attracted to the water molecules and is able to move about
Water molecules have partial negative and positive charges that allow them to attract other charged particles

7. How Ions Form Solids Each ion is strongly attracted to the ions
around it
Solid state is a
result of large
attractive forces
Also result to high
melting points

8. How Ions Conduct
Ions have to be unlocked from their crystal structure (meaning: dissolved)
Ions in liquid state are free to move around and can conduct well
Example: Pure water is a poor conductor but tap water with dissolved minerals is a good conductor.

9. 6.2 Molecular Compound Forms when atoms share a pair of electrons
Bond formed between these atoms is called covalent bond
Usually between non metal and non metal

10. Molecules with Electron Sharing

11. Ball and Stick Model

12. Properties of Molecular Compounds
Exist as solids, liquids or gases
Many are not soluble in water
Often do not conduct electricity
Have a weaker attraction between molecules (compared to ionic compounds)
Have low melting and boiling points

13. Examples 1. Dihydrogen monoxide (H2O or water)
Considered the universal solvent
2. Carbon Dioxide (CO2)
Involved in respiration and photosynthesis
A greenhouse gas

14. Examples 3. Carbon Monoxide (CO)
A poisonous gas that is colourless and odourless
4. Hydrogen Peroxide (H2O2)
Used as a disinfectant

15. Do pg 237 # 1 - 4