1. Physical and chemical properties and changes
properties of matter
Physical and chemical properties and changes

2. Chemistry: big ideas
The use of elements and compounds has both positive and negative effects on society and the environment
Elements and compounds have specific physical and chemical properties that determine their practical uses.
What does that mean?
Individual characteristics of substances determine how they are used.

3. Matter Everything is made of matter.
Your desk
Your shoes
Your lunch
To determine what type of matter something is we use our senses to make observations of its properties.
5 senses?
Sight
Smell
Touch
Sound
Taste

4. Matter
Knowing the properties of matter means knowing how to handle it safely- especially when something goes wrong.
*WHMIS
Tell me about this:
All matter has both physical and chemical properties.

5. Physical properties
Characteristics of a substance that are observed with the senses
Can be observed or measured without changing the composition of the substance
The boiling point of water is 100°C
The melting point of water is 0°C
Can be measured without breaking the molecules apart into hydrogen atoms and oxygen atoms
There are 2 types of physical properties….
Any property that can be observed or measured without the formation of a new substance or without changing the identity of the substance

6. Physical properties Qualitative: Quantitative:
Characteristics that can be described but not measured (i.e. no numerical information)
Ex: the solution is an opaque, dark blue colour
Quantitative:
Characteristics that can be measured numerically
Data represented with numbers
Ex: We have 238 ml of the solution

7. Physical properties Colour Blue, colourless Odour Sweet, pungent State
Qualitative
PROPERTY
EXAMPLE
Colour
Blue, colourless
Odour
Sweet, pungent
State
Solid, liquid, gas
Texture
Soft, smooth, rough
Lustre
Shiny, dull
Malleable
Pliable, hard, soft

8. Physical properties Quantitative PROPERTY EXAMPLE Conductivity
Ability to conduct electrons or heat
Viscosity
Resistance to flow
Melting point*
Melts at ______
Boiling point*
Boils at ______
Density*
Mass to volume ratio
Solubility
Ability to dissolve other substances
Hardness
Ability to scratch other substances

9. Characteristic Physical properties
Physical properties can be used to identify a substance:
Eg) The specific temperature at which a substance changes state is a characteristic physical property
Melting point: temp at which a solid turns into a liquid
Boiling point: temp at which a liquid turns into a gas
Density – Substances have a specific density ratio
The specific temperature at which a substance changes state is a characteristic physical property

10. Water's Unusual Properties
Water has very unique physical properties:
Can exist in 3 states at the same time
Unusually high boiling point
Temperature moderation
Very soluble!
Can dissolve a large variety of chemical substances
Liquid is more dense than solid

11. Chemical properties
Describe the ability of a substance to react with another substance and form a new substance
Eg. Ability of copper to turn green (oxidizing) is a chemical property

12. PROPERTY
EXAMPLE
Reactivity
How elements and compounds react to
create new chemicals or products
Combustibility
The ability of an element or compound to
burn in air
Stability
How easily a substance decomposes
- More stable = longer to break down
Toxicity
Refers to the harm that exposure can cause
to animals and plants

13. Reactivity
A substance’s tendency to react to different substances is a chemical property
Reaction with Water
Sodium  explosion
Calcium carbide  light
Reaction with Oxygen
Iron  rust
Combustion  fire
Reaction with acids or bases
Baking soda and acid produce CO2  makes dough rise

14. PROPERTY PHYSICAL? CHEMICAL? Red colour Density Flammability
Solubility
Reacts with acid to from hydrogen gas
Supports combustion
Bitter taste
Melting point
Reacts with water to form gas
Reacts with a base to form a gas
Hardness
Boiling point
Lustre
Odour

15. Physical Changes Objects do not change their chemical nature
Physical properties change - texture, shape, size, colour, odour
Eg. Baseball bat
Eg. Sugar water

16. Chemical Changes Atoms combine to form new molecules
One or more of the following indicates a chemical change:
Change of colour
Gas produced
Energy released or consumed
Precipitate is formed

17. Physical or Chemical change?

18. Physical or Chemical change?

19. Physical or Chemical change?
Physical change think…
Change in shape
Change in appearance
Chemical change think …
Burning
Cooking
Rusting
Film processing
[Was there production of a new substance?]

20. Physical or Chemical change?

21. Physical or Chemical change?

22. Physical or Chemical change?

23. homework
Using the tables in your notes, add an everyday example of each property