Chapter 2
Properties of Matter
notes on pgs 38-42
Stop reading after “Homogeneous
Mixtures” and before “Solutions,
Suspensions, and Colloids”
Composition
• Example in book – clothing
– What types of fabric are your clothes
made of?
– What are the properties of those fabrics?
– What are the different care instructions
for each?
2.1 Classifying Matter
• Everything is made of atoms
• Atoms combine/bond to make “stuff”
• “stuff” in science is called matter
2.1 Classifying Matter
• Pure Substances
– “fixed, uniform composition”
• All made of the same type of substance
• “fixed” – can’t change
• “uniform” – all the same
– 2 types
• Elements
• Compounds
2.1 Classifying Matter
• Elements
– See PT
• Compounds
– Atoms that have bonded together
2.1 Classifying Matter
• Mixtures
– Non-bonded substances
– Heterogeneous
• The different pieces are visible &
distinguishable
• Cinnamon sugar
– Homogeneous
• The mixture all looks the same
• Ex: salt water
2.2 Physical Properties
• “…any characteristic of a material that can be
observed or measured without changing the
composition of the substances in the material.”
– Viscosity
Resistance to flowing
– Conductivity
Ability to transfer heat
– Malleability
Can be hammered w/o shattering
– Hardness
Scratch-ability
– Melting point
Temp at which solid
liquid
– Boiling point
Temp at which liquid
gas
– Density
Amount of stuff in a given area
Density
Which is more dense?
A
B
Density
Which is more dense?
A
B
Identifying Unknown Metals Write Up
• Purpose (10 pts)
– One sentence
– Why are you doing the lab?
• Materials (10 pts)
– List what materials you are going to use
• Procedure (10 pts)
– List of what you are going to do, step by step
– Be specific!
• Data & Observations (10 pts)
Focus:
– Make a data table
* Learning abt. density
– Don’t forget to label units!
– Be specific!!
* Being specific
• Conclusion (10 pts)
* Following write-up
– 3 short paragraphs
 Summarize purpose and procedure
 Discuss data – interesting parts, points worth noting, etc.
 What did you learn? Did you enjoy it?
Using Properties to ID Materials
• Which properties should you look at?
• When/who would use this?
Using Properties to Chose Materials
• Look at figure 13 on pg 48 (Making Generalizations)
Facts and Figures: iron, nickel, and cobalt
Using Properties to Separate Mixtures
• Filtration
– Separates based on size
– ex
• Distillation
–
–
–
–
Separates based on boiling point
Addressing Misconceptions
Facts and Figures: Tea
ex
Getting a Fresh Start
• Good to know where your water comes from.
• Background – last half
– Ca2+ & Mg2 + = hard water
Soap scum & soap less effective
– Water softeners replace Ca2+ & Mg2+ with Na1+
• Going further
– Activated charcoal
– Reverse osmosis
Test Review - Things to Know
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Types of matter (reading strategy pg 38)
Compounds vs elements
Compounds vs mixtures
Definition of each kind of matter
7 physical properties of matter
Filtration & distillation
Physical vs chemical properties/changes
Chapter 1
– Scientific notation
– Unit conversion
– Scientific method
Test Taking Strategies
• Use the test to take the test
– If you don’t know the answer to a question, skip it! Later in
the test there might be another question that actually gives
you the answer to the question you didn’t know.
• Rationale
– Ex: If we haven’t covered suspensions, solutions, and colloids,
there won’t be a question on it, therefore they won’t be an
answer!
• If there are multiple answers that mean the same
thing, none of them are probably right, unless there
is an answer option that includes all of them.