Concept:

 Periodic table  Group/family  period  Metalloid  Metal  Transition element  Non-metal

 History of Periodic Table  Mendeleev (1869) arranged elements based on atomic mass  Anton van den Broek proposed that elements should be arranged to nuclear charge instead of atomic mass  Moseley confirmed these findings with x-ray spectra and arranged them by atomic number. Therefore, atomic number will increase from left to right.

 H - Hydrogen  Li - Lithium  Na - Sodium  K - Potassium  Be -Beryllium  Mg - Magnesium  Ca - Calcium  Ba – Barium  Fe - Iron  Ni – Nickel  Pt - Platinum  Cu - Copper  Ag -Silver  Au – Gold  Zn - Zinc  Hg - Mercury  B - Boron  Al – Aluminum  C - Carbon  Si - Silicon  Ge – Germanium  Sn - Tin  Pb - Lead  N - Nitrogen  P - Phosphorus  As -Arsenic  Sb - Antimony  Bi – Bismuth  O - Oxygen  S - Sulfur  Se - Selenium  F - Fluorine  Cl - Chlorine  Br - Bromine  I - Iodine  He - Helium  Ar - Argon  Kr –Krypton  Ne – Neon

Metals  (blue area; groups 1-12 except H, and under stair-step line groups 13-15)  Good conductors of heat and electricity  Solid at room temperature (except for Hg)  Reflects light (luster)  Malleable (hammered into sheets)  Ductile (stretched/drawn into wire)

 Alkali Metals  Group 1 (one valence electron)  Softer than most other metals  Silvery/shiny  Most reactive of all metals (reacts rapidly with oxygen and water)  Do not occur in nature in elemental form  Stored (kerosene)  Fr - radioactive

 Alkaline Earth Metals  Group 2 (2 valence electrons)  Not found as free elements in nature  Gives fireworks color, bright red lights, aircraft

 Transition elements  Groups 3-12 (elements in transformation)  Form colored compounds  Often occur in nature as uncombined elements  “Iron Triad” (Fe, Co, Ni – 8, 9, 10)  Used to make steel and other metal mixtures  “Coinage Metals” (Cu, Ag, Au – 11)  Stable, malleable, found in nature as free elements

 Zn, Cd, Hg (group 12)  Used to coat other metals  Cd – rechargeable batteries  Hg – liquid thermometers

 Inner Transitional Metals  ALL are radioactive and unstable  Lanthanides (Atomic Number 58-71)  Actinides (Atomic Number )

Nonmetals  Gases or brittle solids at room temperature  Can form ionic or covalent bonds  Not malleable  Not ductile  Most do not conduct heat or electricity  Generally not shiny  All, except H, are found on right of periodic table (in yellow)

 Group 17 “Halogens”  Most reactive non-metal  7 electrons in outer nrg level, one needed to make it complete  Gains an electron from metal  forms a salt  In gaseous state form reactive diatomic covalent molecules (identified by distinctive colors)  F – most chemically active of all elements  Cl – most abundant halogen  Br – only nonmetal that is liquid at room temp

 Group 18 “Noble gases”  Full outer energy level “happy” so they exist as isolate atoms  Stable & Relatively unreactive

Metalloids  Elements along stair-step line (except for Al)  Can form ionic and covalent bonds with other elements  metallic and nonmetallic properties  Semiconductors

 Mixed groups  Group 13 – Boron Group (Al most abundant metal)  Group 14 – Carbon group  Group 15 – Nitrogen Group  Group 16 – Oxygen Group

 Synthetic Elements  Elements not typically found on Earth  Made in a lab  With exception to Technetium 43 and Promethium 61, each synthetic element has more than 92 protons

 Plutonium (94) used in bombs and control rods of nuclear reactors  Americium – smoke detectors  Transuranium Elements – elements with 92+  Synthetic and unstable; disintegrate quickly  Not considered metals, nonmetals, or metalloids

 Period  Horizontal rows (across)  Use to tell energy level  Group  Vertical columns (down)  Elements within a group have similar properties due to valence electrons  Use to tell valence electrons  Valence electrons  the electrons in the outer most energy level that are available to chemically react  Correlates to the group number for main group elements

 Energy levels (nrg)  1-7 Correlate to periods (rows) on table  1 st nrg level can only hold 2 e. 8 e are needed for each nrg level to make that level complete and stable. Nrg levels closest to nucleus have lower nrg  Level 1 up to 2 e  Level 2 up to 8 e  Level 3 up to 18 e  Level 4 up to 32 e

 Valence electrons for main group elements  Group 1 – 1; give up 1  Group 2 – 2; give up 2  Group 13 – 3; give up 3  Group  Group 15 – 5; gain 3  Group 16 – 6; gain 2  Group 17 – 7; gain 1  Group 18 – 8; gain 0

 Electron cloud structure  Lewis Dot structure