1. Elements, Compounds, and Mixtures

2. Essential Questions What are pure substances?
What are the characteristics of elements?
How can they be used to identify an element?

3. Elements Are a pure substance
Can NOT be broken into a simpler substance physically or chemically

5. Pure substances Have only one type of particle
Particles are called atoms
All atoms are EXACTLY the same

7. Characteristic Properties
Characteristics do not depend on the amount of the element
Physical characteristics:
Boiling point
Melting point
Density,

8. Characteristic Properties
Characteristics do not depend on the amount of the element
Chemical characteristics:
Reactivity with acid
Flammability

9. Identifying Elements Elements are unique.
Elements may share some properties with other elements, but not ALL properties.

10. Identifying Elements Three major categories of elements: Metals
Non-metals
Metalloids

12. Metals Shiny Conduct heat energy Conduct electric current Malleable
Ductile

13. Nonmetals Do not conduct heat energy Do not conduct electric current
Solid nonmetals have a dull appearance.
Brittle
Unmalleable
Examples: Iodine,
sulfur, neon

14. Metalloids Have properties of both metals and nonmetals
Are also called “semiconductors”
Some are shiny.
Some are dull.
Are somewhat malleable and ductile
Ex: Silicon, boron, antimony

15. Metalloids

16. Mini Quiz
1. A sample of matter, either a single element or a single compound, that has definite chemical and physical properties is a(n) A. Metal B. Element C. Metalloid D. Pure Substance

17. Mini Quiz
4. Elements are classified in 3 major categories. Which of the following does not apply? A. Metal B. Non-metal C. Metalloid D. Compound

18. Mini Quiz
2. A property of an element that does not depend on the amount of the element is called a(n)
a. electromagnetic property.
b. finite property.
c. unique property.
d. characteristic property.

19. Mini Quiz
3. An element’s ability to react with acid is an example of a
a. pure substance.
b. physical property.
c. chemical property.
d. melting point.

20. Reference Holt, Rinehart and Winston (2005) INSB 0-03-043217-0