PERIODIC TABLE PERIODIC TABLE

PERIODIC TABLE PERIODS- are the rows, the numbers are principle energy levels (PEL). GROUPS- are columns, based on the numbers of valence electrons. All members have similar properties

PERIODIC TABLE S block: groups 1 and 2 P block: groups D block: groups 3-12 F block: lanthanide and actinide series

METALS

METALS vs NON-METALS METALS NON-METALS Left of staircase Right of staircase Loses e- Gains e- Form (+) ions Form (-) ions Low ionization energy High I E Low electronegativity High electroneg Luster Malleable Ductile Conductors

METALLOIDS METALLOIDS Semi-conductors Properties of both metals + non (+) & (-) ions Brittle solids

Group 15 Non-metals Metalloids Metals

PERIODIC TABLE best metals - lower left best non-metals - upper right

Phases Liquids are Br, Hg Gases include - H, N, O, F, Cl + the Noble gases

GROUP 1 ALKALI METALS Metals Give up 1 electron Highly reactive Reacts violently with water Not found in nature by themselves- only in compounds

GROUP 2 ALKALINE EARTH METALS Highly reactive Not found in nature Harder than the group 1 metals

TRANSITION ELEMENTS TRANSITION ELEMENTS Groups Two oxidation #‘s Less reactive. Make colored ions. Metals - higher melting points.

PERIODIC TABLE Group 15 (N) receives 3e- triple bonds N 2 Group 16 (O) receives 2e- double bonds O 2

HALOGENS Group 17 Most reactive non-metals Gains electrons Negative ions Forms salts High electronegativity High ionization energy gas -liq- sol Diatomic

NOBLE GAS Group 18 Inert gases Non-reactive Complete outer shell Highest ionization energy Least tendency to lose electrons

DIATOMIC ELEMENTS These must have two atoms when they are alone. These Include: H, N, O, F, Cl, Br, I

SYNTHETIC ELEMENTS Are not found naturally Tc (Technetium), Pm and all atomic numbers greater than 92 All are radioactive

RADIOACTIVE No known stable elements Above 82 atomic number

VALENCE ELECTRONS Electrons in outermost shell They are the ones that react They may be gained, lost, or shared

ALLOTROPES Different forms of the same element They each have different properties This is due to their different structures Oxygen and Ozone are allotropes of each other Carbon has four main allotropes: diamond, graphite, coal, buckministerfullerene

ATOMIC RADIUS

The size of the Atom.

ATOMIC RADIUS Down a group, there are more energy levels - larger radius Across the period, there are more protons (more attraction) smaller radius

IONIC RADIUS Size of ions Metals lose electrons : Decrease in radius Loses last energy level Smaller than covalent Non-metals gain electrons: Increase radius

IONIC vs ATOMIC RADIUS

ELECTRONEGATIVITY Ability to attract electrons Higher on the right Fluorine has the most tendency to gain. Francium the lowest

IONIZATION ENERGY The Energy needed to remove outermost electron How easily elements give up an electron Metals (low) Non-metals (high) As you go Down a Group, ionization energy gets lower because electrons are further out!

SUCCESSIVE IONIZATION ENERGIES Ionization energies become successively larger because electrons are closer and more tightly held

TRENDS Across a Period: Atomic # increases # of valence electrons increases Nuclear charge increases Atomic radius decrease Electronegativity increases Ionization Energy increases Metallic character decrease

TRENDS Down a group: Atomic # ­ increase Principle energy levels increase Atomic radius increases Electronegativity decreases Ionization energy decreases Metallic character increases