classification of matter. what is matter? anything that occupies space and has mass
TRANSCRIPT
Classification of Matter
What is matter?
• Anything that occupies space and has mass
What is matter made of?
• Substances: matter that is an element or a compound
So how do we classify matter:
- By the materials matter is made up of
- 4 states of matter
Example:
• How would you classify a
pencil?
- Wood
- Graphite
- Eraser
Break it down to the to its simpler parts!!!!
Elements
• The unit that makes up all matter are atoms– If all atoms of the sample of matter have the
same identity they are called elements (see periodic table of elements)
• Example: Oxygen
Compounds
• What happens when two or more elements come together?– They form a Compound
• Example: H20 – H is an element, O is an element, together they form
the compound water
How about table salt?
• Table salt is a compound:– NaCl
• Na is an element, Cl is an element– Together they form a compound
Mixtures
• What happens if you combine salt and water?
– When you combine two or more substances that can be separated by physical means you have a mixture!
• Salt can be separated from water by evaporation!!!
Back to the pencil!
• The pencil is a MIXTURE:– Wood (compound)– graphite (element)– Eraser (compound)
Solutions
• Salt water – mixture– Can you see the salt in the water?
• No• Homogenous Mixture –
– A material in which two or more substances are spread out evenly and cannot settle out when standing
Homogenous mixture = Solution
Heterogenous Mixtures
• A mixture in which different parts can be easily distinguished
– Example: Pencil, Peanut Butter and Jelly Sandwich
Categories of Heterogenous Mixtures
• Colloids – Heterogenous mixture that never settles– Example: Milk
– How can you tell it’s a colloid?• By the Tyndall Effect
– The scattering of light by the particles in the mixture
Suspension
• Some mixtures are neither solutions nor colloids
– They are known as a suspension• Is a heterogenous mixture containing a liquid in
which visible particles settle out when standing– A muddy river
» How is this different from a solution or colloid?
- Particles carried in suspension will settle out