Matter_ Mixtures_ Pure Substances

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Aim: What is matter?
Do Now: A cup of gold colored metal beads was
measured to have a mass 425 grams. By water
displacement, the volume of the beads was calculated
to be 48.0 cm3. Given the following densities, identify
the metal.
Gold: 19.3 g/mL
Copper: 8.86 g/mL
Bronze: 9.87 g/mL
HOMEWORK: GO ON THE SCHOOL WEBSITE. SELECT
“HOMEWORK #1 MATTER AND PROPERTIES”. ON A
SEPARATE SHEET OF PAPER RECORD YOUR ANSWER
AND EXPLAIN YOUR REASONING FOR YOUR CHOICE.
Matter
•Matter is anything that has mas mass and volume
•Mass and volume are examples of extensive properties
•Extensive properties are properties that depend on the
amount of matter in a sample
•Intensive properties are properties that depend on the
type of matter in a sample, not the amount of matter (i.e.,
density)
Physical change vs. Chemical Change
PHYSICAL CHANGE
•During a physical change, some
properties of a material change, but
the composition of the material does
not change
CHEMICAL CHANGE
•During a chemical change, the
composition of the matter always
changes
•A new product is not formed
•Chemical changes produce new
substances with different chemical
make-ups and properties than the
original substance.
•Examples: aluminum foil is cut in half,
water evaporates from the surface of
the ocean, juice freezes
•Examples: milk goes sour, gasoline is
ignited, your body digests food, metal
rusts
•Physical changes can be classified as
reversible or irreversible
Mixtures
•A mixture is a physical blend of two or more components.
•Based on the distribution of components, mixtures can be
classified as heterogeneous mixtures or as homogeneous
mixtures
•Heterogeneous mixtures are a mixture in which the
composition is not uniform throughout.
• Oil and vinegar, chicken noodle soup
•Homogeneous mixtures or solutions are mixtures in which the
composition is uniform throughout.
• oil, vinegar, cup of coffee, salt water
Elements and Compounds
•An element is the simplest form of matter that has a unique
set of properties.
•Oxygen, hydrogen
•A compound is a substance that contains two or more
elements chemically combined in a fixed portion.
•Salt, sugar
•Compounds can be broken down into simpler substances by
chemical means, but elements cannot.
-Particles are not uniformly
distributed. Particles are physically
combined.
-Particles are uniformly distributed.
Particles are physically combined.
-Simplest form of matter. Ex: O2
-Two or more different elements
chemically combined. Ex: H2O
Sample Problems
Which substance can not be decomposed into simpler
substances?
(1) ammonia
(2) aluminum
(3)methane
(4)methanol
Sample Problems cont.
Which statement describes a characteristic of all
compounds?
(1) Compounds contain one element, only.
(2) Compounds contain two elements, only.
(3) Compounds can be decomposed by chemical means.
(4) Compounds can be decomposed by physical means.
Sample Problems cont.
Which formula represents a binary compound?
(1) NH4NO3
(2) CH4
(3) CH3CoCH3
(4) CaCO3
Sample Problems cont.
An example of a heterogeneous mixture is:
(1) soil
(2) sugar
(3) carbon monoxide
(4) carbon dioxide
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