Chemistry
Last year you were expected to:
•Classify matter based on its physical properties including
magnetism, physical state, and the ability to conduct or insulate
heat, electricity, and sound;
•Demonstrate that some mixtures maintain the physical properties
of their ingredients;
•Identify changes that can occur in the physical properties of the
ingredients of solutions such as dissolving sugar in water ; and
•Observe and measure characteristic properties of substances that
remain constant such boiling point and melting point.
Everything in the universe is made of matter.
Some examples of matter are water, soil, air, and even you.
What is matter?
Matter is anything that has
mass and takes up space
(volume).
Matter is identified by its
physical properties.
What is a property?
Properties are the
characteristics of matter.
What is a physical
property?
A characteristic of a
substance that can be
observed with the five
senses or measured
without changing the
substance into
something else is called
a physical property.
Some common examples
of physical properties of
matter are odor, taste,
hardness, texture, color,
shape, mass, and volume.
What is mass?
Mass is how much matter
is contained in an object.
It is measured in grams
using a balance.
What is volume a measurement of?
Volume is a measurement of how much space
an object takes up.
Volume of a rectangular prism can be found by
multiplying length x width x height using cm3.
Volume of a liquid is measured in a graduated
cylinder using the metric unit milliliters.
Volume of irregular objects can be found by
dropping the object into a graduated cylinder
containing water and measuring the change in
the volume of water. This method is called
water displacement.
1 mL = 1 cm3
Some other physical properties are:
Magnetism is the ability of a material to exert a
force that either attracts or repels other materials.
Some well know materials with magnetic
properties are iron, some steels, and the mineral
lodestone.
The state of matter a substance is in is another example of a physical
property. There are 5 states (or phases) of matter. The most common
are solid, liquid, and gas. The other two are plasma and BoseEinstein condensate. A substance can change states by adding or
taking away energy.
Each state has definite
characteristics. A solid
has a definite shape and
volume. A liquid has a
definite volume but
takes the shape of the
container it is in. A gas
takes the volume and
shape of the container it
is in.
Read more @ http://www.chem4kids.com/files/matter_intro.html
Each substance has a specific boiling point, melting point, and
freezing point. Boiling point is the temperature where a substance
changes from a liquid to a gas. Melting point is the temperature at
which a substance changes from a solid to a liquid. Freezing point is
the temperature at which a liquid changes to a solid.
Melting, Freezing, and Boiling Point of Common Substances
Substance
Melting/Freezing Point
Boiling Point
Water
0°C
100°C
Hydrogen
-259°C
-253°C
Oxygen
-219°C
-183°C
Alcohol
-112°C
78°C
Ammonia
-78°C
-35.5°C
Gold
1,063°C
2,600°C
Mercury
-39°C
357°C
Olive Oil
-6°C
300°C
Another physical property is a substances ability to conduct or
insulate heat, electricity, and sound.
Metals are good conductors of
heat, electricity, and sound.
Plastic, fiberglass,
rubber, Styrofoam,
and cotton are
examples of good
insulators.
Some other physical properties are:
Brittleness – substance is easily broken or shattered
chalk
Ductility – ability to be drawn into a wire
Malleability – can be hammered
or pressed without breaking
Elasticity – stretches
Luster – quality or condition of
shining by reflected light
dull
shiny
Electrolyte - liquid that conducts electricity
Viscosity – the resistance of a liquid to
flowing under applied force
Opacity – the degree to which a substance
reduces the passage of light
opaque vase
Transparency – the degree to which a
substance freely permits the passage of light
transparent
butterfly
transparent vase
A mixture is a composition of two or more substances that are not
chemically combined with each other and are capable of being separated.
Heterogeneous mixtures do not have a uniform composition or even
distribution of each substance in the mixture.
birdseed
fruit salad
Coke with ice
air
oil & water
Solutions are mixtures with the molecules in a completely even
distribution making them homogeneous.
Salt mixed with water
creates a solution
because the salt will
evenly distribute
throughout the water
molecules. This
solution can be
separated by
evaporating the water
leaving the salt behind.
Solutions can be
solids dissolved in
liquids or even
gases dissolved in
liquids. There can
also be gases in
other gases and
liquids in other
liquids
There are two parts to a solution. A solute is the
substance that gets dissolved. The solvent is the
substance that does the dissolving. In the
example of the salt and water solution, the salt is
the solute and the water is the solvent.
solute = salt
solvent = water
6th grade Objectives:
In sixth grade you are expected to:
•Demonstrate that new substances can be made when two or more
substances are chemically combined and compare the properties of
the new substances to the original substances;
•Classify substances by their physical and chemical properties; and
•Define matter and energy.
What is matter?
Matter is anything that has
mass and takes up space
(volume).
What is a chemical
property?
A chemical
property is a
characteristic
that is observed
when a
substance
interacts with
another
substance.
An example of a chemical
property is the way some substances
burn and some do not called
flammability. Another chemical
property is reactivity. Some
substances that chemicals react to
are water, oxygen, light, electricity,
heat, and acids.
Describe a physical change.
A physical change is a change in
the appearance of matter, like
size, shape, or state, but the type
of matter is unchanged.
What are some examples of physical
changes?
Some examples of physical
changes might be chopping wood,
bending wire, sugar or salt
dissolving in water, and ice
melting.
Describe a chemical change.
A chemical change is a change
that produces a new substance
with properties that are different
from the original substances.
Chemical changes usually release
energy in the form of heat, light,
or electricity. A substance going
through a chemical change can
change color.
Give some examples of chemical
changes.
Some examples of chemical
changes are milk souring,
burning wood, iron rusting, and a
cake baking.
What is required for physical
and chemical changes to occur?
Energy is required for matter to
move, react, or transform in physical
or chemical changes.
What is energy?
Energy is the ability to do work or cause
change.
What is an acid?
An acid is a substance that has a sour
taste and is corrosive.
What are some examples of an
acid?
Lemon juice, vinegar, citric acid, and
HCl or hydrochloric acid are examples
of acids.
What is a base?
A base is a substance that feels slippery,
tastes bitter, and denatures proteins.
What are some examples of bases?
Laundry detergent and shampoo are
examples of bases.
What is an indicator?
An indicator is any chemical that
changes color in an acid or a base.
What is an example of an indicator?
BTB, Universal Indicator, Phenol Red,
and Red Cabbage Juice are examples of
indicators.
Describe an element.
An element is a type of substance
with only one kind of matter.
What is a substance called that
has more than one kind of matter?
A compound has more than one kind of
matter.
Water (H2O) and salt (NaCl) are examples of
compounds.