1. We are Learning Today... 1. To understand the arrangement of the periodic table. 2. To be able to explain the difference between a metal, a nonmetal, a period and a chemical family.

2. What do you know about this table??

3. The Periodic Table All of the known elements are organized in a chart called the periodic table. The periodic table was developed by Dmitri Mendeleev in the 1870s. The periodic table is a very orderly and systematic way of arranging all the known elements. So, what are these systems used to organize the periodic table???

4. The Periodic Table Dmitri Mendeleev (1834-1907) Russian (Siberia) scientist (youngest of 17 children) scientists needed a way to systematically organize their careful observations of the elements classify the elements according to shared characteristics or regularities organized into columns (families) and rows (periods) 1st PT was arranged according to the increasing atomic mass current PT arranged according to the increasing atomic number = PROTONS Periodic LAW -- The properties of the elements recur periodically when the elements are arranged in increasing order by their atomic numbers

5. Columns = Families = Groups share commom characteristics (physical and chemical) are called by special names because they share similar features like valence electrons, bonding and other characteristics they undergo the same types of physical and chemical reactions Periods = Rows do not show similar characteristics Row 1 = Period 1 Row 2 = Period 2

7. CLASSIFICATION OF ELEMENTS - The first orderly arrangement has to do with whether or not the element is classified as a METAL (conducts electricity), NON-METAL (do not conduct electricity), or METALLOID (conducts very little but have characteristics of both other groups).

8. Physical Properties of Metals and Nonmetals Metals: - conduct electricity and heat - can be hammered into sheets (malleable) and stretched into wires (ductile) - shiny appearance (lustre) - all are solids at room temperature (except mercury) Non-Metals: - at room temperature, some are gases, some are solids, and one (bromine) is a liquid - solid non-metals are brittle, cannot be stretched into wires, and are not very shiny - do not conduct electricity or heat very well

9. The Periodic Table Metals are found on the left-hand side of the periodic table, non- metals are found on the right- hand side. These are separated by a stair step line on the right side of the table, and the metalloids are found on either side of this line.

10. A second orderly arrangement of the elements within the periodic table is into vertical columns called CHEMICAL FAMILIES. Chemical families are subgroups made up of metals, non- metals, or metalloids. All of the elements within a chemical family have similar chemical properties. Chemical Families (aka groups)

11. EXPLAINING CHEMICAL FAMILIES -Elements in the same family (or group) always have the same number of electrons in the outer (Valence) shell, and the same chemical properties. -For example, the elements in group 1 all have only 1 electron in their outer shell. -The number of electrons in the outer shell, determines how reactive each element in that family will be. - Because group 1, only has one element in their outer shell, they are very reactive with just about any substance (air, water, gas, etc). - The opposite is true of group 8, they have a full outer shell, so they are very un-reactive.

12. Vertical groups are called FAMILIES. There are 8 families.

15. Alkali Metals normally are solids (hydrogen has to possible locations on the PT) are so soft that they can be cut with a knife cut surfaces are shiny but it dulls quickly as the metal reacts with oxygen very reactive excellent conductor of electricity bond 1 time only sodium vapor lamps are used as fog lights/street lights as less energy needed and the yellow light is very intense react with water very quickly to produce an alkali or basic solution and hydrogen gas evolves Sodium Potassium

17. Alkaline Earth Metals reactive metals harder, denser, stronger metals (than the alkali metals) and have higher melting points solids conduct electricity form 2+ charged ions shiny metals but will dull when reacted with oxygen magnesium is a low density metal that is stronger than other metals....when alloyed with other metals is useful for aircraft/aerospace applications (strong but light)/sports equipment/bicycles/backpacks/tennis rackets milk of magnesia/limestone/marble/blackboard chalk/ gymnastics, weightlifting, and rock climbing Magnesium Calcium

19. Transition Metals very hard, with high melting points and boiling points. high electrical conductivity and malleability of the transition elements Form positive ions with a wide range of charges complexes form characteristic colored solutions and compounds may not dissolve very well in water weakly magnetic (only strongly magnetic elements are iron, cobalt and nickel)

21. Group III - Boron Group Not found free in nature, but are all present in various minerals and ores Aluminum is the most widely used element in this group Boron is most commonly used for Borax, flares, and glass High melting points and high densities Except for aluminum they have very little commercial value

23. Group IV - Carbon Group The carbon family elements tend to be fairly unreactive Have widely variable physical and chemical properties Elements exist free in nature and in compounds Carbon, tin and lead can all be found in the Earth’s crust, and are readily mined Silicon is found in mineral deposits

26. Group V - Nitrogen Group Except for nitrogen, the elements are solid at room temperature Not many other similar characteristics Group VI - Oxygen Group Found free in nature and in compounds Very electronegative (pull electrons towards them) Phosphorus Bismuth Sulphur Selenium

28. Halogens Form diatomic molecules in their elemental state Very reactive, very electronegative Very different physical properties but similar chemical properties

30. Noble Gases generally non-reactive full valence shells no bonds occur (or rarely) neon and argon used in illuminated signs helium used for party balloons, blimps, weather balloons Argon Neon

31. - a third orderly way of arranging elements within the periodic table was to put them into horizontal groups called PERIODS

32. -JOHN DALTON'S ATOMIC THEORY, which stated that each element had a different ATOMIC MASS, helped scientists put the elements in order. -Using Dalton's ideas, and the atomic mass that he had assigned to each element, Mendeleev built a PERIODIC TABLE OF ELEMENTS that put the elements in order from smallest to largest atomic mass (across the periods and down the groups). - He also arranged the elements by increasing atomic number (going from left to right across the table). How did Mendeleev know which elements went where?