1. NOTES: Physical and Chemical
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2. LESSON 2 Properties of Matter
Unit 2 Lesson 2 Properties of Matter
LESSON 2
Properties of Matter
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3. Physical Properties of Matter
Unit 2 Lesson 2 Properties of Matter
Physical Properties of Matter
A characteristic of a substance that can be observed without changing the identity of the substance is called a physical property.
You use your senses to observe physical properties.
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4. What are physical properties of matter?
Unit 2 Lesson 2 Properties of Matter
What are physical properties of matter?
Mass
Volume
Density
The state of matter (solid, liquid, gas)
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5. What are physical properties of matter?
Unit 2 Lesson 2 Properties of Matter
What are physical properties of matter?
Electrical conductivity - how well electric currents moves through it.
Thermal conductivity – how well it transfers heat.
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6. What are physical properties of matter?
Unit 2 Lesson 2 Properties of Matter
What are physical properties of matter?
Solubility - the ability of a substance to dissolve in another substance.
Malleability - the ability of a substance to be rolled or pounded into various shapes.
Ductility – the ability of a substance to be pulled into a wire.
Magnetic
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7. What are physical properties of matter?
Unit 2 Lesson 2 Properties of Matter
What are physical properties of matter?
Luster – shine.
Melting Point - the temperature at which it changes from a solid to a liquid.
Boiling point - the temperature at which a substance boils.
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8. Chemical Properties of Matter
Unit 2 Lesson 2 Properties of Matter
Chemical Properties of Matter
A chemical property is the ability of a substance to change into a new substance with different properties.
Chemical properties can be identified by the changes they produce.
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9. What are chemical properties of matter?
Unit 2 Lesson 2 Properties of Matter
What are chemical properties of matter?
Flammability - the ability of a substance to burn.
Reactivity - the ability of a substance to interact with another substance and form one or more new substances.
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10. Physical and Chemical Changes
Unit 2 Lesson 3 Physical and Chemical Changes
LESSON 3
Physical and Chemical Changes
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11. Unit 2 Lesson 3 Physical and Chemical Changes
Physical changes
Physical change: a change that affects one or more physical properties of a substance.
appearance
shape
size
change in state (solid, liquid, gas)
texture
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12. Unit 2 Lesson 3 Physical and Chemical Changes
Chemical change: the process in which one or more substances change into entirely new substances.
Chemical changes are not the same as chemical properties.
Example: Burning is a chemical change;
Flammability is a chemical property.
When particles and chemical bonds that make up a substance are rearranged, a chemical change has taken place.
Chemical changes can be influenced by temperature.
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13. How can you tell a chemical change has happened?
Unit 2 Lesson 3 Physical and Chemical Changes
How can you tell a chemical change has happened?
Signs of a chemical change: 
Odors
The production of gas (fizzing, foaming)
A precipitate forms (a precipitate is a solid that falls out of solution)
Energy changes (heat, sound, light)
Changes in temperature
Changes in color
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14. Chemical Reactions Substances used in a reaction are called reactants.
Unit 2 Lesson 3 Physical and Chemical Changes
Chemical Reactions
Substances used in a reaction are called reactants.
After the reaction is complete, the new substance that formed is called the product.
During a chemical reaction bonds between reactants are broken down and new bonds are formed in the products.
Example:
2 Hydrogen (H) + Oxygen (O)  Water (H2O)
[ Reactants ] [--Product--]
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15. Chemical Reactions Unit 2 Lesson 3 Physical and Chemical Changes
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16. Unit 2 Lesson 3 Physical and Chemical Changes
Chemical Reactions
Activation energy is the energy required to get a chemical reaction started.
EXAMPLE-
When baking cookies the oven provides activation energy
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17. Unit 2 Lesson 3 Physical and Chemical Changes
Chemical Reactions
Exothermic Reaction – energy is released and temperature increases.
Energy can be released in two general ways light and heat .
EXAMPLE
*CH4 + 2O2 - CO2 + 2H2O KJ
*All combustion reactions are examples of exothermic reaction .
-Exothermic Reactions are symbolized as: reactants - Products + energy  
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18. Unit 2 Lesson 3 Physical and Chemical Changes
Chemical Reactions
Endothermic Reaction – energy is absorbed and temperature decreases.
Endothermic reactions will cool the area around them by absorbing the necessary energy from the surroundings, decreasing the temperature.
EXAMPLES
* Chemical cold packs are examples of endothermic reactions.
* photosynthesis, where plants absorb energy as sunlight to
turn carbon dioxide and water into glucose and oxygen.
-Endothermic Reactions are symbolized as: Reactants + energy  Products
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