BURNING A CANDLE
• After melting, is the wax still
wax?
Yes, so Physical Change
• After burning, is the candle wick
still a candle wick?
No, so Chemical Change
MR. BEAN MEETS CHEMISTRY
• As you watch the
video of Mr. Bean,
what are some
indicators of a
chemical change
(chemical reaction
that you notice)?
SolidFixed VolumeFixed Shape
Least Kinetic Energy
LiquidFixed Volume
No fixed shapeModerate
Kinetic Energy
GasNo Fixed VolumeNo Fixed Shape
Most Kinetic Energy
Melting
BoilingEvaporating
Freezing Condensing
Sublimation
Deposition
Remember: States of matter changes are physical changes. The identify of the substance
stays the same.
Physical and Chemical Properties of Matter
Physical Properties/Changes Chemical Properties/Changes
Graphite — the layered structure of the carbon atoms gives graphite its physical properties.
The pattern of the atoms gives the
substance its physical properties.
Physical Properties
Physical Properties
Physical Changes– can be observed without changing the identity
of the substance( color, hardness, melting point & density)
– is only a change in any physical property of a substance
– matter can change from one state to another (liquid to a gas)
Some physical changes would be• boiling of a liquid• melting of a solid• dissolving a solid in a liquid • grinding or crushing• Condensation - when gas
becomes a liquid
Physical Properties and Changes Recap
• The characteristics of a substance that can be observed without changing the identity of the substance are called physical properties.▫ Examples:
Color Shape Texture Volume Mass Density
• A physical change is any change in any physical property of a substance, not in the substance itself.▫ Examples
Breaking a piece of clay Stretching a rubber band Melting ice into liquid water Dry Ice sublimating into gas
Chemical Properties and Chemical Changes
• Chemical properties of a substance are defined by the chemical changes it undergoes.
• Chemical changes transform the substance into a new identify.
• Chemical change or chemical reaction is the transformation of one or more atoms or molecules into one or more different molecules.
Chemical Properties and Changes
• Chemical properties describe how substances can form new substances.
• A chemical property is any of a material’s properties that becomes evident during a chemical reaction.▫ Examples:
Combustibility (ability to burn) Easily oxidized (ability to rust) Toxicity (level of harm to organisms) Reactivity with other chemicals Types of chemical bonds that will form
• The change of one substance into another substance is called a chemical change.▫ Examples:
The burning of wood The rusting of iron Mixing baking soda and vinegar to produce carbon dioxide
gas
Physical and Chemical Changes
Indicators of a
Chemical Change
• Color Change▫ Can be tricky to interpret▫ Some color changes are just a
mixture, not a chemical change Physical change – mixing food
coloring into water (mixture) Chemical change – iron
rusting due to oxygen (something new)
• Gas produced▫ Has to be a new substance, not
boiling!• Temperature change
▫ Gets hot – exothermic reaction▫ Gets cold – endothermic
reaction• Precipitate formed
▫ A solid is formed when reacting two or more fluids
• Odor change▫ A new smell!
• Light or sound production▫ Boom!
Physical vs. Chemical
• Examples:
– melting point
– flammable
– density
– magnetic
– tarnishes in air
physical
chemical
physical
physical
chemical
• Examples:
-rusting iron
-dissolving in water
-burning a log
-sublimation
-grinding spices
Chemical and Physical Change Practice Quiz #1
Chemical
Physical
Chemical
Physical
Physical
Practice Quiz #1; Practice Quiz #2
Physical vs. Chemical
COMPLETE CHEMISTRY PACKET USING ONLINE
TEXTBOOK
Mr. Ganey’s Webpage Science Booknotes (Textbook) Chemistry Textbooks
Matter and Energy Textbook Chapter 2
Extension:
Make vocabulary flash
cards from Chapter 1
Study Guide (#1-18)
and Chapter 2 Study
Guide (#1-10)