States of Matter. What is matter ? 5/24/2015 2 Matter- anything that has mass and volume 5/24/2015 3.

States of Matter

What is matter ?

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Matter- anything that has mass and volume

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Physical Properties

•Can be observed or measured without changing the identity of the matter.

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•Example: You don’t change the identity of an apple to find it’s volume or see that it is red

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Thermal Conductivity: The rate at which a substance transfers thermal energy (heat)

Example: Cup of hot chocolate warms your

hands

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Solubility: The ability of a substance to

dissolve into another substance.

•Example: Flavored drink mix dissolves into water

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•Ductility: The ability of a substance to be pulled into a wire.

Example: Copper Wire is ductile

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•Malleability: The ability of a substance to be rolled

or pounded into thin sheets.

• Example: Aluminum can be rolled into sheets to make aluminum foil

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• You use physical properties all the time.

• For example, physical properties help determine if your socks are clean (odor) or if you can fit all your books into your backpack (volume).

•Density: The mass per unit volume•Density = mass

volume

D= m

v04/18/23

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Density Practice

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Practice Problems•Example: What is the density of an object whose mass is 20g and whose volume is 10 mL?

•D= ?•1. Write the equation

D= m v

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• 2. Replace m and V with numbers

• D= 20g = 2 g/mL

10mL

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•Example 2: What is the density of an object whose mass is 35 g and whose volume is 7 mL?

•Write the steps and solve yourself.

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• 1. D= m v

2. D= 35g 7mL

3. D= 5 g/mL

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Chemical Properties

Describe matter based on its ability to change into new

matter with different properties.

Example: Wood can be burned to create

new matter (ash and smoke)

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Flammability- The ability to

burn

Ex: Wood has the ability to

burn

Nonflammability

- an object will not burn

Example: Pots & pans

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Just so you know….

Reactivity the ability of 2 or

more substances to combine & form a

new substance

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Reactivity with Oxygen- OxidationWhen iron is

exposed to oxygen and

it rustsEx: Rusty nail

Nonreactivity with oxygen: Substances or

objects that will not rust.

Ex: The bumper on a car

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How are physical and chemical

properties different?

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What’s the difference?

•Physical Properties- Can be

measured/observed and do NOT change what something is

made of

Chemical Properties:

Describes how something will react.DOES change the

chemical nature

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Signs of a Chemical Change

•Changes in color•Heat is produced •Fizzing and Foaming•Production of Soundor Light

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Physical Change•A change that affects one or more physical properties of a substance.

Example: Breaking a piece of chalk in two pieces.

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Examples of Physical Changes

•Freezing water for ice cubes

•Sanding a piece of wood

•Cutting your hair

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•Bending a paper clip

•Melting a stick of butter

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Chemical Change•Two or more substances are changed into a new substance

•Not the same as Chemical Properties

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Remember……•Chem. Props describe the ability of a substance to go through a chemical change

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What happens during a chemical change?

•When you bake a cake, you combine eggs, flour, sugar, oil, and other ingredients.

•Each ingredient has its own set of properties

•But if you mix all the ingredients together, you get something completely different.

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•The heat of the oven and the interaction of the cake ingredients cause a chemical change.

Physical Change: A change in appearance only; DOES NOT CHANGE the identity of the matter

Examples:Size change

Shape changeState change ( solid to liquid)

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Chemical Change: Produces new matter with different properties. The identity of the matter does change

Examples:Color Change

Heat produced or removedFizzing & Foaming

Smell ChangeLight/ Sound Produced

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EndothermicEnergy is gained by a substance

- Think “endo”= enter- Heat removed = cooler

Example:Baking soda and vinegar absorbs heat and gets colder.

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ExothermicEnergy is expelled. Can give

off heatThink “exo” = exit

Example:Oxidation – gives off heat

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States of Matter

-Physical forms in which a substance can exist

•Solid•Liquid

•Gas

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Solid•definite shape and definite volume

•Molecules are very close together

•Molecules vibrate in place

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Examples•Rock•Tree•Loaf of bread•Puppy•Iron•Cell Phone•i-pod

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Liquid•No definite shape; takes the shape of its container

• Ex: When you pour water from a beaker into a graduated cylinder does it stay in the shape of the beaker? Nope!

•definite volume

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•Molecules move around

•Examples: •Coffee•Water

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Gas•No definite shape

•No definite volume

•Molecules completely break away from each other.

•There is empty space between the molecules.

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Plasma

•No definite shape or volume

•Molecules have broken apart

•Plasma Conducts electric currents;GASES DON’T

Examples:AurorasFluorescent LightsLightning 04/18/23

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