1. Properties of Matter
Section 15.2

2. Warm up What is matter? What are the three states of matter?
Fill in the tables with one difference between each of the following:
Element and compound
Compound and mixture

3. Objectives Identify substances using physical properties.
Compare and contrast physical and chemical changes.
Identify chemical changes.
Determine how the law of conservation of mass applies to chemical changes.

4. Introduction
What properties can be used to describe the items in the following figure?

5. Physical properties
Any characteristic of a material that you can observe without changing the identity of the substance.
Examples of physical properties are:
Color, size, shape, mass, volume, density, melting point, boiling point, attraction to magnet and the ability to flow.

6. Some physical properties describe the behavior of materials or substances.
Examples are copper and gold.

7. Using physical properties to separate
How can you separate a mixture of iron filling and sand?
How can you separate a mixture of seeds and sand?

8. Physical change

9. Physical change

10. Use physical change to separate
Distillation

11. Chemical properties and changes
A chemical property is a characteristic of a substance that indicates whether it can undergo a chemical change.
Examples: flammability,

12. Detecting chemical change
Chemical change: a change of one substance to another.
Examples of chemical change

13. Chemical change

14. Clues of chemical change
Smell,
change in color
formation of gas
formation of a precipitate
pop sound
production of heat
cooling
formation of bubbles, light, foaming…

15. Using chemical change to separate
Cleaning tarnished silver.
Tarnish is a chemical reaction between silver metal and sulfur compounds in the air.
We can remove tarnish by placing the tarnished silver item in warm water, baking soda and aluminum foil.
Many metals are separated from their ores and then purified by using chemical changes.

16. The conservation of mass
Matter is neither created nor lost during a chemical change.
The mass of all substances that are present before a chemical change equals the mass of all substances that remain after the chemical change.
Example: when a chemical reaction takes place, the total mass of reactants equals the total mass of products. If 18 g of hydrogen react completely with 633 g of chlorine, how many grams of HCl are formed?
H2 + Cl HCl

17. Wrap up What is a physical property? What is a chemical property?
Distinguish between a physical and chemical change.
Examples of a physical and chemical change and properties.
Law of conservation of mass

18. Practice problem page: 463 # 1 and 2 Quiz in section 15.2
Home Work
Page: 465 # 1 to 6
Practice problem page: 463 # 1 and 2
Quiz in section 15.2