Groups of the Periodic Table of Elements

1. Groups of the Periodic Table of Elements Metals vary in Shininess - Malleablility- Ductility- Conductivity- Reactivity-

2. Alkali Metals – Group 1http://www.youtube.com/watch?v=m55kgyApYrY • The most reactive metals. • React with other elements by losing 1 electron • So reactive they are never found alone in nature. • Examples—Na sodium and K potassium

3. Alkaline Earth Metals-Group 2 • React by losing 2 electrons • Good conductors of electricity • Not as reactive as Group 1 but more reactive than most metals • Are also never found uncombined in nature • Examples Mg magnesium and Ca calcium

4. Transition Metals-Groups 3-12 • Includes familiar metals such as Fe iron Cu copper Au gold Ag silver Ni nickel • Most are hard and shiny • Good conductors of electricity • Not very reactive other than they rust-oxidation • Many form colorful compounds (used in paints)

5. Metals in MixedGroupsGroups 13-15 • Only some are metals –MIXED groups • Less reactive • Al aluminumSn tin Pb lead

6. Carbon Family-Group 14 • Carbon is the only element in Group 14 that is a nonmetal • These elements gain, lose, or share 4 electrons • Carbon is found in all living things = organic • Most fuels contain carbon

7. Nitrogen Family-Group15 • N nitrogen and P phosphorus are nonmetals • Gain or share 3 electrons

8. Oxygen Family-Group 16 • Gain or share 2 electrons • Contains 3 nonmetals • O oxygen • S sulfur • Se selenium • Oxygen is highly reactive and can combine with almost every element.

9. Oxygen • Oxygen exists as O2 (a diatomic molecule) in the air we breathe • Oxygen also forms O3 called ozone (a triatomic molecule) which collects in the upper atmosphere where it screens out harmful radiation from the sun. • Ozone is a dangerous pollutant at ground level because it is highly reactive. • Oxygen is the most abundant element in Earth’s crust and the second-most abundant element in the atmosphere. (The first is nitrogen.)

10. Halogen Family-Group 17 • Halogens are nonmetals except for At astatine • Fl flourineCl chlorine Br bromine and I iodine • are the most reactive nonmetals • Have similar properties-gain or share one electron • Salt forming • Very reactive • Uncombined elements are dangerous to humans

11. More on Halogens • Fl is so reactive it reacts with almost every other known substance. • Water will burn in Fl • Cl gas is extremely dangerous- • but ok in small amounts to kill bacteria in water. • Br liquid will burn skin

12. Noble Gases-Group 18 • Do not ordinarily form compounds because atoms of noble gases do not usually gain, lose or share electrons. • Stable-unreactive • 8 valence electrons (except helium which has 2)

13. Hydrogen • Can not be grouped into a family because it is so different.

14. Metalloids • Along the border between metals and nonmetals • Have characteristics of both metals and nonmetals • Varying ability to conduct electricity depending on • temperature • light • impurities • makes them useful in semiconductors.

15. Lanthanides • Top row at bottom of periodic table • Soft, malleable, shiny metals • High conductivity • Mixed with more common metals to make alloys. • Alloy-mixture of a metal with at least one other element.

16. Actinides • Row of elements at bottom of Periodic Table below the Lanthanides. • U uranium is used to produce energy in nuclear power plants • Nuclei are very unstable-break apart quickly • Synthetic Elements atomic # above 92 are man made by particle accelerators which force atoms to crash together. • Exception—Neptunium and ___have been found in nature