Who invented the Periodic Table? Note that Mendeleev Had to switch I and Te In order to get the Chemical characteristics Correct by column. (Why were they off? How he predicted the unknown elements using the table. Below Boron Below AluminumBelow Silicon Try Your Luck. Use the cards I have given you to figure out how you could arrange them in a Periodic Table. Remember that the table has rules going up and down AND across. There are missing cards. Figure out what they are and where you would place them. An example of what you should have ended up with. The Gray cards are the missing ones. SSong about MendeleevkuQ0Um4Wcz0http://www.youtube.com/watch?v= kuQ0Um4Wcz0 ALLthe elements in ORDER songWtFtEMhttp://www.youtube.com/watch?v=zUDDi WtFtEM MoseleyFirst to use Atomic Number Based his findings on a new technology, Atomic Line Spectra. This Technology is now used to identify elements in the stars. The Periodic Table by Electron Configurations P6 Abbreviated Table of Electron Configurations S1,2 D1-10 F 1-14 P1-5 Alkalai Metals Alkaline Earth Metals Transition metals Halogens Noble gases Lu Lr Which Family would want to LOSE an electron to become NOBLE? Which family is most similar to the Alkalai Metals? Difference between Groups 1 and 2? Characteristics of two families. The Alkali Metals Very reactive with Halogens and Water When they react with water they form very BASIC solutions (lots of OH). They also react with air so they are kept in oil to keep the air from contacting them. The Alkaline Earth Metals React with Oxygen Slightly less reactive than group 1 Harder and with higher melting points than the Alkali metals (group 1) alkalai metals in water and alkaline earthsBrainiac and alkalai metals Two more groups Halogens Also very reactive Often react with the Alkali metals so that they take the extra electron from the alkali metals to make themselves NOBLE. F and Cl are gases at room T but Br is a liquid and iodine and astatine are solids. Noble Gases Usually dont react with anything In 1962 a compound was made between xenon and fluorine so no longer called INERT. Halogens(27 minutes in length) More detail on HalogensNoble Gases Which family absolutely WOULD not want to lose an Electron (because it would be further from NOBLE)? So the TREND across the table says that .. What is Ionization energy? What is an ION? An ATOM that LOSES or GAINS electrons. Why would an atom want to LOSE or GAIN electrons? To Become NOBLE! So Ionization energy is the amount of energy required to kick out one electron. Because the electrons OTHER THAN the valence electrons get in the way of the influence of the nucleus, there is less force holding the VALENCE electrons in. This is called ELECTRON SHIELDING. TrendAcross the tableDown the table Ionization Energyincreasesdecreases Atomic Radiusdecreasesincreases Electronegativityincreasesdecreases What is atomic radius? Radius Going down a column. Group 1 Yet across. Group 1 (Alkali Metals) Group 18 (Noble Gases) WHY? More pull by the electrons and protons pulls the electrons closer to the nucleus. + E- e- WHY? More pull by the electrons and protons pulls the electrons closer to the nucleus. + E- e- TrendAcross the tableDown the table Ionization Energyincreasesdecreases Atomic Radiusdecreasesincreases Electronegativityincreasesdecreases What happens to the atomic radius going down a column. Group 1 (Alkali Metals) Group 18 (Noble Gases) Electronegativity The opposite of Ionization energy: ionization energy requires LOOSING an electron. Electronegativity means the desire to GAIN an electron. Which is THE MOST ELECTRONEGATIVE ELEMENT? Why? BECAUSE IT WANTS TO GRAB AN ELECTRON TO FILL ITS OUTER SHELL! TrendAcross the tableDown the table Ionization Energyincreasesdecreases Atomic Radiusdecreasesincreases Electronegativityincreasesdecreases What is Electronegativity? Think of it as the OPPOSITE of IONIZATION ENERGY with the SAME TREND. It means the desire to ADD an electron. The MOST ELECTRONEGATIVE ELEMENT IS FLUORINE On the other hand, Francium does NOT want to get another electron!! TrendAcross the tableDown the table Ionization Energyincreasesdecreases Atomic Radiusdecreasesincreases Electronegativityincreasesdecreases