matter - dorettaagostine.com 2 ss.pdf · a mixture is a physical blend of two or more substances....
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Matter
Matter is anything that
has mass and takes up
space.
Mass is the amount of
matter that an object
contains.
Mass is the amount of matter
Weight is the force of gravity
on an object
Is the amount of space
an object takes up
Matter that is uniform and has
a definite composition is
called a substance
Pure substances = one type of
matter
Solid
Liquid
Gas
◦Has a definite shape
◦Has a definite volume
◦Does not take the shape of its
container.
◦Form of matter that flows
◦Fixed volume
◦Takes the shape of its container
◦Most are incompressible
◦Do expand when they are heated
Take the shape of their
container
Take the volume its container
Are compressible
What is the difference between a gas and vapor?
Gases: are a gas at room temperature
Vapors: gaseous state of a substance that is normally a liquid or solid at room temperature.
A quality or condition of a
substance that can be observed
or measured without changing
the substance’s composition.
Melting point
Boiling point
Density
Color
Solubility
Odor
Hardness
A physical change is one that alters a
given material WITHOUT changing
its composition, such as:
◦Cutting
◦Grinding
◦Bending
◦Melting/freezing (change of state)
Are the following pure
substances? Lemonade
Ice
Table salt
A mixture is a physical blend of two or
more substances.
There are two kinds of mixtures:
Heterogeneous: not uniform in
composition
Homogeneous: completely uniform in
composition. “Solution” is the special
name given to homogeneous mixtures.
Any part of a system that is uniform
in composition is called a phase.
A homogeneous mixture (solution)
has one phase. Something with
two or more phases is
heterogeneous.
Solutions form in all three states.
Gaseous solutions- air is an example. Air
acts as the solvent as liquids evaporate.
Liquid solutions- soft drinks and many
other examples exist in everyday life.
Solid solutions- alloys are solid solutions
A heterogeneous mixture in which
the particles are so large that they
can be seen and will settle out unless
the mixture is stirred or agitated.
The simplest form of matter
that can exist under normal
conditions
The building blocks for all
other substances
Can be separated into simpler substances
◦Only by chemical means
◦Ex. Burning sugar-
Before the sugar is cooked it is a
compound, after, it is just an element
When one or more substances
form into a new substance or
new substances
Example: rust
◦Iron + O2 → iron oxide (rust)
Two sides to a chemical
reaction
The reactants, or the starting
substances
The products, substances that
are formed
The ability of a substance to
undergo a chemical reaction and
to form new substances
◦Chemical properties are only
observed when there is a
chemical change
Energy change (+ or -)
Color change
Odor change
Solid formed
Liquid formed
Gas formed
Chemical changes may only be
reversed by a chemical means
Physical changes may be reversed
because they do not involve a change
in composition
The law of conservation of mass:
states that in any physical change
or chemical reaction, mass is
neither created nor destroyed, it is
conserved
The mass of the reactants equals
the mass of the products