2. Objectives 1. Use a periodic table to name elements, given their symbols 2. Use a periodic table to write the symbols of elements, given their names 3. Describe the arrangement of the periodic table 4. List the characteristics that distinguish metals, nonmetals, and metalloids
3. Elements Pure substances that cannot be decomposed by chemical means Serve as building block of matter Each element has characteristic properties Organized on periodic table in groups according to their properties
5. Elements on Periodic table Atomic number 6 C 12.011 Carbon Chemical Symbol Atomic Mass Element Name
6.
7. Types of elements Metals Properties Luster Malleable Ductile Good conductor of heat and electricity
8. Copper – representative metal Reddish color Metallic luster Found in chalcopyrite and malachite Melts at 1083 celcius Boils at 2567 celcius Malleable and ductile
9. Nonmetals Many are gases at room temperature (F, O, N, Cl) Brittle Nonconductors of heat and electricity Dull ( no luster)
10. Phosphorus – a nonmetal One of 5 solid nonmetals Two forms – red phosphorus (melts at 597 celsius) White phosphorus (melts at 44 celsius) Stored underwater, it ignites in air Too reactive to exist in nature in pure form All living things contain phosphorus
11. Metalloids Stair-step line separates metals from nonmetals on periodic table Metalloid is an element that has some properties of metals and some of nonmetals All are solids at room temp. Less malleable than metals but not as brittle as nonmetals Tend to be semiconductors
12. Noble gases Elements in group 18 of periodic table UNREACTIVE Not identified until 1962 All gases at room temp. Neon, Helium, Argon, krypton, Xenon