1. The Classification of Matter
SCH3U
Unit 1: Matter, Chemical Trends and Chemical Bonding

2. What is Chemistry?

3. Matter Matter is anything that takes up space
It is anything that has mass and volume
We describe and identify matter based on its properties (characteristics).
Physical properties
Chemical properties

4. Physical Properties
Physical properties are characteristics that can be observed without changing the chemical composition of a substance.
Qualitative properties are physical properties that can only be described in words.
Quantitative properties are physical properties that can be measured or expressed numerically.

5. Chemical Properties
Chemical properties are characteristics that are observed when the chemical composition of the material is changed (ie: a chemical change takes place).

6. Qualitative Properties Quantitative Properties
Properties of Matter
Physical Properties
Chemical Properties
Qualitative Properties
Quantitative Properties
Physical state
Melting point
Reactivity with water
Colour
Boiling point
Reactivity with air
Odour
Density
Reactivity with O2
Crystal shape
Solubility
Reactivity with acids
Malleability
Electrical conductivity
Reactivity with pure substances
Ductility
Thermal conductivity
Toxicity
Hardness
Combustibility
Decomposition

7. Remember…? Physical and chemical changes
A physical change doesn’t affect the chemical identity or composition of matter
Ex. Change in state
A chemical change alters the chemical composition of matter, resulting in at least one new substance being formed
Four signs of a chemical change:
Colour change
Production of gas
Formation of precipitate
Energy released or absorbed (heat/light)

8. Classifying Matter Pure Substances: have a definite, fixed composition
Elements: substances that can not be broken down into simpler substances
Compounds: chemical combination of two or more elements. They always contain the same proportion of elements.
sodium (Na)
sodium chloride (NaCl)

9. Classifying Matter Mixtures: a combination of two or more substances.
Solutions (homogeneous mixture): mixtures with uniform properties and composition.
Mechanical mixture (heterogeneous mixture): mixtures where the individual components are visible.

10. Classifying Matter MATTER PURE SUBSTANCES MIXTURES ELEMENTS COMPOUNDS
SOLUTIONS
(HOMOGENEOUS)
MECHANICAL MIXTURES
(HETEROGENEOUS)