Transcript How are Compounds and Mixtures Similar? Different?

How are Elements,
Compounds and
Mixtures Similar?
Different?
Note that an element:
• consists of only one kind of
atom
• cannot be broken down into a
simpler type of matter by either
physical or chemical means
• can exist as either atoms or
molecules
Did you know?
• A molecule consists of two
or more atoms of the same
element.
How do elements bond together?
You must first learn why atoms bond
together. We use a concept called "Happy
Atoms." We figure most atoms want to be
happy, just like you. The idea behind Happy
Atoms is that atomic shells like to be full.
That's it. If you are an atom and you have a
shell, you want your shell to be full. Some
atoms have too many electrons (one or two
extra). These atoms like to give up their
electrons. Some atoms are really close to
having a full shell. Those atoms go around
looking for other atoms who want to give up
an electron.
For example, oxygen atoms have 6 electrons
in their 2nd electron field, leaving 2 slots
open. One oxygen atom will bond with 2
hydrogen atoms to create water. Now, the
oxygen’s outer electron field is full making it
stable and HAPPY! 
Note that a compound:
• consists of atoms of two or more different
elements bound together,
• can be broken down into a simpler type of
matter (elements) by chemical means (but
not by physical means),
• has properties that are different from its
component elements, and
• always contains the same ratio of its
component atoms.
Which ones are examples of
compounds? Molecules?
Common Compounds
• Table Salt
– Sodium and chlorine
• Water
– Hydrogen and oxygen
• Carbon Dioxide
– Carbon and oxygen
• Sugar
– Carbon, hydrogen, and oxygen
• Baking Soda
– Sodium, hydrogen, carbon, and oxygen
Note that a mixture:
• consists of two or more
substances not chemically
combined
• can be separated into its
components by physical means
• often retains many of the
properties of its components
Look at a sedimentary rock. It is a
mixture. See how you can see the
different pieces in the granite.
Can you think of anything
else that is a mixture?
Mixtures come in different shapes and
sizes. Sometimes they don’t even look like
mixtures. One type of mixture that can fool
the eye is called a solution. An example of a
solution is Kool-Aid.
Solution: mixture that appears to be
a single substance but is composed
of particles of two or more
substances that are evenly
distributed.
There are 2 parts to a solution:
• Solute: substance that is
dissolved
• Solvent: substance in which
the solute is dissolved
Which one is the solute?
Solvent?
Concentration: measure of the
amount of solute dissolved in a
solvent
Look at the picture of
at the What color
the Look
marbles.
has the highest
concentration?
More Mixtures…
• Suspension: mixture
in which particles of
a material are
dispersed
throughout a liquid
or gas but are large
enough to settle out.
More Mixtures…
• Colloid: mixture in which the particles
are dispersed throughout but are not
heavy enough to settle out.