TOPIC: Properties of Matter Do Now: A sample of CO2(s) and a

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NEW UNIT: UNIT 3 fold next
section in your notes
TOPIC: Properties of Matter
Do Now:
Anything that has
1) Define Matter:
mass and occupies
space
2)Fill in page 2 in packet
Properties – used
to characterize
matter
Physical –how
they look
Chemical – how
they react with
others
Physical Properties
• Describe the appearance and
form of matter
Words:
• color, texture, luster, odor, solid,
liquid, gas
Measurements:
• a number and a unit
• A sample of CO2(s) and a sample of
CO2(g) different in their
1) chemical composition
2) empirical formula
3) molecular structure
4) physical properties
Other physical properties include
Density, boiling point (BP), and melting
point (MP)
(where can you find the density of Al? Fe?)
Solubility in water (g/ml)
(how well it dissolves in water)
Intensive
Properties: sample
size DOES NOT
matter
Other physical properties like volume
and mass depend on sample size
Extensive
Properties: sample
size matters
Chemical Properties
• Describe how matter behaves in
presence of other matter
• Describe how matter changes
into another kind of matter
– Flammable
– Corrosive
– Ability to neutralize acids or bases
Physical or Chemical?
•
•
•
•
Reddish brown - physical
Forms new substances with HNO3 - chemical
MP = 1085C - physical
Density = 8.92 g/cm3 - physical
• Reacts to form green
copper carbonate
• Shiny - physical
• Malleable - physical
• BP = 2570C - physical
- chemical
Matter goes through changes
Changes
Physical –
identity remains
the same
Chemical –
identity of
matter changes
Physical Change
• The form or appearance of sample
may change but identity remains
same
– Cutting, crushing, grinding, tearing
• Dissolving is physical change
• Think of sugar in water
• still have sugar – you just spread it
out with water molecules in
between
• C6H12O6(s)  C6H12O6(aq)
Aq = dissolved in water
• Phase changes are physical changes
• No new substance is created
(chemical formula stays the same)
• Ex:
• ice melting: H2O(s)  H2O(l)
• water boiling: H2O (l)  H2O(g)
Chemical Change
• chemical change - identity of
matter is changed
• new substance with unique
properties is formed
• The chemical formula changes
• Ex: 2H2O(l)  2H2(g) + O2(g)
Burning
• Common name for oxidation reaction
• Burning means reacting with oxygen
• Burning is chemical change, because
original substance is changed into new
kinds of matter
Ex: COMBUSTION
CH4(g) + 2O2(g)  CO2(g) + 2H2O(g)
Evidence of Chemical a Chemical
Change
• Bubbles (formation of a
gas)
• Color change
• Heat
• Light
• new substance form (if
2 liquids mix and solid
is formed, we call this a
precipitate(ppt))
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