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CHAPTER 2
Properties of Matter
PROPERTIES OF MATTER
Extensive-depends on the amount
of matter in a sample ex: volume,
mass, texture
Intensive-depends on the type of
matter in a sample ex: density,
viscosity, melting point
EXTENSIVE PROPERTIES
It depends on the amount of
matter in a sample
Mass (grams)
Weight (newtons)
volume (mL or cm3)
INTENSIVE PROPERTIES
 Depends on type of matter
 Density(at STP)
- boiling point
 texture
- melting point
 odor
- color
 taste
- ductility
 hardness
- solubility
 malleability
- tenacity
 conductivity - brittleness
STATES OF MATTER
SolidLiquidsGases4th state?
What is plasma?
5th state?
NOVA Bose Einstein Constant
Liquids
• Molecules have room to slide over
each other
• Have no definite shape, but have a
definite volume.
• Not easily compressed
Gases
• Molecules move freely to fill the
container
• Have no definite volume or shape
• Easily compressed
PHASE CHANGES
PHASE CHANGES AND ENERGY
Exothermic- heat is released
Endothermic- heat is absorbed
Is the evaporation of water
exothermic or endothermic?
Explain.
PHASE CHANGES AND
ENERGY
Entropy- a measure of disorder of a system
The more ordered a system is, the more
entropy it has – for example a clean, organized
room has less entropy than a messy room.
Which has more entropy, a solid or a gas?
PHYSICAL CHANGES
During a physical change, the
properties of the material changes, but
not the composition of the material
Can be classified as reversible or
irreversible
Examples:
MIXTURES
Mixture-physical blend of two or
more components
Heterogeneous
ex:
Homogenous (solution)
ex:
ALLOYS
Alloy – homogenous mixture of
metals
Sterling silver- 93% silver 7% copper
Surgical steel- Fe – 67%, Cr - 18%,
Ni-12%, Mo- 3%
Spring steel- Fe- 98.6%, Cr- 1.0% ,
C- 0.4%
SEPARATING MIXTURES
What are some ways that we can
separate mixtures?
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Separating mixtures by
physical means
Filtering
By hand
Boiling- fractional distillation
Freezing
Melting
Evaporating
Dissolving
Crystallizing
Magnetism
SEPARATION OF MIXTURES
Distillation
Filtration
TYPES OF MIXTURES
Homogeneous
Heterogeneous
ELEMENTS AND COMPOUNDS
Element- simplest form of matter with
a specific set of properties
Compound- contains two or more
elements chemically combined
Compounds can be broken down into
simpler substances by chemical means,
elements cannot
ELEMENTS AND COMPOUNDS
Elements are represented by
symbols
Compounds are represented by
chemical formulas, groups of
element symbols
ELEMENT SYMBOLS
CHEMICAL SYMBOLS
1st letter always upper case
Each element has its own
2nd and 3rd always lower case
Represents one atom (or mole)
of the element
Co vs. CO
Ni vs. NI
Chemical Formula – the
“recipe” for a compound.
• Tells what elements are in the compound.
• Tells # of atoms of each element.
– Ex. H2O = 2 atoms of hydrogen and 1 atom of
oxygen
– Ex. NaCl
C6H12O6
H2SO4
COMPOUNDS
NaCl
C6H12O6
Which represents the element,
compound and mixture?
Element (diatomic) = b
Compound = c
Mixture = a
CHEMICAL CHANGES (RXN)
During a chemical change, the
composition of matter always
changes
Reactant
Product
INDICATORS OF CHEMICAL
CHANGE
Formation of precipitate
Production of a gas
Change in pH
Energy change
Color change
Light
Matter
Pure
Substances
Elements
Compounds
Mixtures
Homogenous
Heterogeneous
CONSERVATION OF MASS
- During a chemical reaction, the
mass of the products is always
equal to the mass of reactants
- Law of Conservation of Mass
Chemical Change =
Chemical Reaction
Which of the following is not a
chemical change?
A. Paper being shredded
B. Steel rusting
C. Charcoal burning
D. Newspaper yellowing in SMART
the sun
Response Qu
To set the properties right click and select
SMART Response Question Object->Properties..
2. Which phrase best describes an
apple?
A. Heterogeneous mixture
B. Homogenous compound
C. Heterogeneous substance
D. Homogenous mixture
3. Which element is paired with the
wrong symbol?
A. sulfur, S
B. nitrogen, N
C. potassium, P
D. calcium, Ca
4. Which of these properties could
not be used to distinguish between
table salt and sugar
A. Boiling point
B. Melting point
C. Density
D. Color
5. The state of matter characterized
by a definite volume and an indefinite
shape is a
A. Solid
B. Liquid
C. Mixture
D. Gas
6. Which description below correctly
identifies air?
A. Compound
B. Heterogeneous mixture
C. Element
D. Homogeneous mixture
7. Which description below correctly
identifies carbon monoxide?
A. Compound
B. Heterogeneous mixture
C. Element
D. Homogeneous mixture
8. Which description below correctly
identifies zinc?
A. Compound
B. Heterogeneous mixture
C. Element
D. Homogeneous mixture
9. Which description below correctly
identifies pepperoni pizza?
A. Compound
B. Heterogeneous mixture
C. Element
D. Homogeneous mixture
10. Magnesium metal burns vigorously
in oxygen to produce the compound
magnesium oxide. Use the Law of
Conservation of Mass and the table
below to determine the mass of
oxygen used in the reaction.
Mass of magnesium
Mass of oxygen
6.5 g
?
Mass of magnesium
oxide
10.8 g