1. General Science ’07-’08 Unit 5 The Elements + Periodic Table

2. What is an Element? The simplest type of substance. They can’t be broken down into anything simpler.

3. Six Properties of Metals Metals are to the left of the staircase on the periodic table. 1)Luster- ability to reflect light (they appear shiny) 2)Magnetic- ability to attract certain metals Only three: Nickel, cobalt, and iron 3) Malleable- able to bend and make shapes without breaking

4. Properties of Metals cont. 4) Ductile- ability to be stretched and pulled into wires. 5) Conduct electricity- allows the flow of electrons. Copper is a good example of being ductile and able to conduct electricity 6) Color- used to identify specific metals (gold-yellow; iron-grayish-silver; copper-reddish-orange)

5. Metals in Your Body Calcium Strengthens bones and teeth Controls heart rate Helps contract muscles Found in dairy products Potassium Proper working of nervous system Helps contract muscles Found in bananas, oranges, potatoes

6. Metals in Your Body cont. Sodium Proper nervous system function Controls muscle contraction Found in table salt and other foods Iron On red blood cells as hemoglobin Helps transport oxygen through the body Low iron= anemia

7. Discovering Non-metals Properties opposite of metals Dull, not lustrous Brittle, not malleable or ductile Poor conductors of heat and electricity

8. Important Non-metals Hydrogen In the air we breathe and in water Nitrogen Atmosphere is 78% nitrogen Used by plants to grow Carbon In all living and once-living organisms

9. More important non- metals Oxygen Gives life to humans and fire Chlorine A poisonous gas Found in table salt Made into bleach Fluorine Found in toothpaste as fluoride

10. Understanding Metalloids Metalloids are elements that have properties of both metals and nonmetals. All have luster (they shine)

11. 4 uses for Boron 1.Borax- added to water to “soften” it 2.Prevents “ring-around-the-tub” 3.Boric acid- helps treat infections 4.Used in rocket fuel

12. Silicon Combined with oxygen, it forms sand (silicon dioxide), which, when melted, forms glass Fiber optics for sound, telephone, internet It’s a semiconductor Used in computer chips, circuit boards Used on tiles lining the bottom of space shuttles