properties of matter physical & chemical properties mrs. parnell adapted from mrs. wolfe- glhs
Post on 03-Jan-2016
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Chemistry – Study of the properties of matter and how matter changes
•Matter and energy are the two basic components of the universe
Matter•Material that makes up an object
•Has mass•Occupies space•Exist in 3 states
Physical Properties are UNIQUE!
• A substance has UNIQUE physical PROPERTIES that DEFINE it.
• What substance is:– White, small crystals (solid)– M.P. 212º F, B.P. 1621º F– No odor, Density = .001
• Look up these physical properties in a manual….– It’s SALT!
Physical Properties are observable.
• Physical properties can be OBSERVED.
• Physical properties DO NOT change the chemical nature of matter
• Color, Shape, Odor, Texture• Melting Point• Boiling Point• Physical State
– Liquid, solid, or gas
• Density
Physical properties – do not change the chemical nature of matter
• Hardness• Conductivity – thermal and
electrical
• Ductility – bendable?
• Malleability – poundable?
• Luster - shine
• Viscosity – resistance to flow
• and many more….
Describe the Physical Properties of …
• Aluminum
• Steel
• Which is best suited for a lightweight can of pop?
• Which is best suited for a can of green beans that need to be stacked in piles for months?
A Physical Property: Density
• The number of atoms in a given space.
• Density = mass
volume
• Which is more dense?• B, more atoms in the
same volume!
Practice Problem:• Calculate the density of a CUBE of steel.
• D = m/v
• D = 88/8 = 11 g/cm3
Mass = 88 g2 cm
Viscosity - a liquid’s resistance to flowing
High viscosity: liquid flows slowly (cold syrup)Low viscosity: liquid flows fast (vinegar)
HIGH
LOW
So Far We Have Discussed Physical Properties…
• But substances also have CHEMICAL PROPERTIES.
• Chemical properties – characteristics of a PURE SUBSTANCE that describes its ability to change into a different substance
Testing for Chemical Properties
• To observe chemical properties of a substance, you must try to CHANGE it into another substance
• Tests that can be used:
• Flammability• OXIDATION• Reactivity• Ability to TARNISH
Physical vs. Chemical Properties
• Physical properties are OBSERVABLE.
• Chemical properties can only be observed when the substance is CHANGING.
Physical vs. Chemical Properties
Substance
Rubbing Alcohol Clear liquid Flammable
Red Dye Red liquid Reacts with Chlorine and loses color
Baking Soda White powder Reacts with Vinegar (bubbles indicate a gas has been produced)
Physical Property
Chemical Property
Changes of Matter
• Chemical Changes
• NEW substance with NEW PROPERTIES!
• Example: Bake a Cake; Spoil some Milk– They are NEW, DIFFERENT substances!
• Physical Changes
• SAME substance with SAME PROPERTIES!
• Example: Break a piece of chalk– It’s still CHALK!
Identify these as Physical or Chemical Changes…
Cutting Your Hair
Dissolving Sugar in Water
Burning Wood
Rust Forming on Metal
Separating a Mixture
Battery “Dies”
Physical Change
Physical Change
Physical Change
Chemical Change
Chemical Change
Chemical Change
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