THE PERIODIC TABLE

ORGANIZATION OF THE PERIODIC TABLE Periodic Law: The properties of elements repeat themselves at regular intervals when arranged in order of increasing atomic number

Groups Periods Horizontal rows Also known as families Vertical columns Contain elements with similar properties Periods Horizontal rows Period number equals number of energy levels

G R O U P E R I O D

Groups are divided into..... Main Group or Representative Elements **Groups IA-VIIIA or 1-2, 13-18 Transition Elements or Transition Metals **Groups IB-VIIIB or 3-12

group IIA alkaline earth metals Family Names group IA alkali metals group IIA alkaline earth metals group VIIA halogens group VIIIA noble gases

Alkali Metals most reactive metals Group (IA) 1:

Group (IIA) 2: Alkaline Earth Metals Reactive metals

most reactive nonmetals Halogens most reactive nonmetals Group (VIIA) 17:

Noble gases Stable Group (VIIIA) 18:

Groups 3 - 12: transition metals

inner transition elements (2 rows at the bottom)‏ lanthanide series – top row actinide series – bottom row

Classification of the Elements Elements can be classified as either: 1. Metals 2. Non-metals 3. Metalloids

Metallic character

Metals

Physical Properties of Metals luster (shiny)‏ Ductile-able to be drawn into a thin wire Malleable- able to be pounded into a thin sheet good conductors of heat and electricity All solid at room temperature *exception- mercury is a liquid at RT

Chemical Properties of Metals Loses electrons to become positively charged ions **ion- an atom that has gained or lost electrons to become positively or negatively charged Reactive with water or elements in the atmsophere

Nonmetals

Physical Properties of Nonmetals brittle dull poor conductors of heat and electricity Can be solids, liquids, or gases at room temperature

Chemical Properties of Nonmetals Will gain electrons to become negatively charged ions.

Metalloid -border the diagonal line between metals and nonmetals, have some properties of both metals and nonmetals; not very shiny, most gray or white, fairly good conductors Metalloids

Periodic Trends

Periodicity- the tendency to repeat at regular intervals Periodic Trends Periodicity- the tendency to repeat at regular intervals

Decreases across a period Atomic Radius Increases down a group Decreases across a period

Which has a larger atomic radii? 1. Na or K 2. Mg or P Atomic Radius Which has a larger atomic radii? 1. Na or K 2. Mg or P Put the following in order of decreasing atomic size. F, B, Li, C, Be Ge, Pb, Sn, C, Si

Ionization energy- energy needed to remove an electron from an atom Decreases down a group Increases across a period

Ionization energy- Which has a larger ionization energy? 1. Na or F 2. Ca or Ba

Alkali metals-most reactive metals (Fr is the most reactive metal)‏ Reactivity Alkali metals-most reactive metals (Fr is the most reactive metal)‏ Halogens-most reactive nonmetals (F is the most reactive nonmetal)‏

decreases across a period Non metals- decreases down a group Reactivity Metals: increases down a group decreases across a period Non metals- decreases down a group increases across a period

Electronegativity- measure of tendency to attract electrons Metals tend to lose electrons; have low electronegativity (Fr has the lowest)‏ Nonmetals tend to gain electrons; have high electronegativity (F has the highest)‏

Summary of Trends across a period down a group Ionization energy increases Electronegativy increases Metallic properties decrease Atomic radii decreases across a period Ionization energy decreases Electronegativity decreases Metallic properties increase Atomic radii increases down a group