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What’s the Matter?
Defining Matter
• define matter
• classify an item as matter or not matter
You will be able to:
• Items that are clearly matter are all objects, or
things, that are tangible.
• Energy and ideas are not matter, but they
involve matter.
• Matter has some sort of dimension and
substance to it.
A good definition should work 100% of the time.
Here are some textbook definitions of matter:
• Matter: Anything that has substance and takes up
space.
• Matter: Anything that has mass and volume.
windcloudsmusic
Everything that has mass and takes up space
is matter, yet some things do not consist of
matter.
Here is a list of 10 examples of non-matter.
Basically, any type of energy or any abstract
concept is an example of something that is not
matter.
time sound
light color
love thoughts
gravity microwaves
heat memories
information reflections
Why aren’t light and heat
matter?
The universe consists of matter and energy. The
Conservation Laws state that the total amount of matter
and energy are constant in a reaction, but matter and
energy may change forms.
Energy describes the ability to cause change. While
matter may have energy, they are different from each
other.
One easy way to tell matter and energy apart is to ask
yourself whether what you observe has mass. If it
doesn't, it's energy!
Examples of energy include any part of the
electromagnetic spectrum, which includes visible light,
infrared, ultraviolet, x-ray, microwaves, radio, and gamma
rays.
Other forms of energy are heat (which may be considered
infrared radiation), sound, potential energy, and kinetic
energy.
Another way to distinguish between matter and energy
is to ask whether something takes up space. Matter
takes up space. You can put it in a container. While
gases, liquids, and solids take up space, light and heat
do not.
Usually matter and energy are found together, so it can
be tricky to distinguish between them. For example, a
flame consists of matter in the form of ionized gases and
particulates and energy in the form of light and heat.
You can observe light and heat, but you can't weigh
them on any scale.
summary
• Chemists study all kinds of matter.
• Matter is everything that has substance and
takes up space, or that has mass and
volume.
Your brain is an example
of matter, ideas are not.
What is matter?
• Matter is anything that has mass and
takes up space.
• Matter can be classified by extensive or
intensive properties.
• Extensive depends on the amount of
matter in the sample.
• Intensive does not depend on the amount
but the type of matter in the sample.
• Property: A characteristic of a
substance.
• Matter has observable and measurable qualities.
• We can use general properties to identify substances.
All substances have properties…
Example:
People can be identified by their …
Face (shape,
expressions) Voice HeightFinger prints
Eye color Hair color Teeth DNA
Physical Properties: Characteristic of a
substance that can be observed without
changing the substance into something else.for example: mass, color, hardness, size, texture, odor
Chemical Properties: characteristics involved
when a substance interacts with another
substance to change its chemical make-up.for example: pH, flammability, rusting (oxidizing), gassing
Properties are used to identify, describe
and classify matter.
examples of physical properties
commonly used in chemistry:
• state, freezing point, boiling point, melting point, viscosity, density, luster and many more.
–viscosity - The resistance of a liquid to flowing.
Low viscosity-water, rubbing alcohol
High viscosity-honey
Physical properties of matter are categorized
as either: Intensive or Extensive:
•Intensive - Properties that do not depend on the amount of the matter present.
– color, odor, luster
– malleability, ductility, conductivity
– Density
Extensive – Properties that change when the size of the sample changes.
• mass, volume, length
• total charge
Chemical properties
• A common chemical property is reactivity.
– Reactive to oxygen
– Reactive to air
– Reactive to water…
Note that chemical properties
aren’t EASY to observe,
unlike physical properties.
examples of chemical properties
commonly used in chemistry:
• Flammability, corrosivity, oxidation state, and more
oxidation - The loss of electrons.
When a substance is oxidized, it’s properties change
for example –
silver tarnishes
metals rust
Did you know?
Fruit exposed to the air is oxidized (the oxygen steals
electrons from the compounds in the fruit’s cells) and
turns brown.
The process is very similar to the
rusting process of metals. The
oxidized form of these compounds
is different from the unoxidized form
and is, unfortunately, unappealing
to eat.
antioxidantsMany 'superfoods' are advertised as containing
antioxidants. An antioxidant is a compound that
reduces the oxidation of other compounds.
In theory, consuming antioxidants will help our bodies
fight off the harmful effects of oxidation, keeping our
cells and enzymes happy and healthy. In other words,
eating things like blueberries and chocolate will
help our insides from looking like
browning fruit.
Remember: You can change substances physically and
chemically.Physical Changes -- Do Not form new substances.
Chemical Changes -- Do form new substances.
Physical change : a change that affects one
or more physical property
Test for a physical change - can it be
undone?
Because physical changes do not fundamentally alter the
identity of the substance, they are often easy to undo.
How do you know if it is a
chemical or physical property?
If it can Change and can’t be reversed, it’s
CHemical
Test for a chemical change – can it
be undone?
Are the properties of the
new substance different
than the original properties?
How can you tell if a physical or
chemical change has taken place?
• A precipitate is formed • density changes
• Heat is released • a color change
• Gas is produced • light or sound is produced
• pH changes • A new odor is formed
Is it a physical or chemical change?
Breaking glass
Frying an egg
Shaking pop
Ice pack
Burning a match
Freezing
water
Hand warmers
Cooking
macaroni
Rusting car
Boiling water
Chopping
veggies
Baking a cake
Chemical Reactions
• remember - Clues that a chemical change has occurred are: – energy transfer (heat increase or decrease), change in
color,
– gas production,
– formation of a precipitate (solid formed)
Cool chemical
reactions
Chemical Reactions
• During a chemical change, the composition of matter always changes.
– A substances present at the start of the reaction are called the reactants.
– The substances present at the end of the reaction are called the products.
reactants product
Chemical Reactions
• During a chemical change, the composition of matter always changes.
– During any chemical reaction, the mass of the reactants and the products must equaleach other.
• This is the Law of Conservation of Mass.
During ordinary physical or chemical
processes matter can neither be created
nor destroyed. It can only change forms.
Law of Conservation of Mass
indicators
• Indicators are used extensively in lab testing.
• Indicators are usually organic dyes.
• Indicators change color
based on the pH of the
substance – so you
know whether
something is acidic or
basic.
• They do not cause and
are not part of the
reaction
How do You Know You Made
Something New?
HCl + NaHCO3 → ???
Hydrochloric acid + sodium bicarbonate look like
they are reacting chemically. Why?
reactants products
• Was the gas one of
the products?
• Can you demonstrate
conservation of
mass?
• What do you think the
product is?
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