Objectives 19-1 Distinguish periods and rows on the periodic table Identify an element as a metal, nonmetal or metalloid Identify the valence electrons for elements in groups 1-2, Create electron dot structures for elements in groups 1-2, Identify an element’s properties based on the group it belongs to Compare and contrast elements based on their placement on the table.

Atomic Number Symbol Name Average Atomic Mass You Know This!!!! 1 H Hydrogen 1.008

Periods DEF: Horizontal rows –Elements gain one proton and one electron as you go from left to right across the periods. –Change properties Numbered 1-7

Groups DEF: Vertical columns –AKA: Families Numbered 1 through 18. Elements in each group have similar properties

Same valence electrons –DEF: electrons in outermost energy level used for bonding Group number Valence electrons

Groups 3-12 and the 2 pull out sections –No set pattern –Varies even within the group

Electron or Lewis Dot Structures DEF: uses symbols and dots to show valence electrons Used to show how elements will bond –Will they gain or lose electrons

Pattern to use X

Group 1 Group 2 Group 13 Group 14 LiMgBC Group 15 Group 16 Group 17 Group 18 AsSFNe

Bonding with Lewis Structures Middle atom is usually atom with the most open spots Octet Rule –DEF: Elements want 8 VE –Bonding accomplishes this

Periodic Table Groups

Metals State of matter at room temperature –All but one are solid Valence electrons –Easily lose Group Numbers –1, 2, 3-12, pull outs and parts of 13, 14 and 15

Characteristics Good conductors of heat and electricity High densities High melting points Luster Malleable Ductile

Nonmetals State of matter at room temperature –Gases, liquids or brittle solids Valence electrons –Most gain Group Numbers –All of 18, parts of 14, 15, 16, 17 –Plus Hydrogen

Characteristics Are not shiny, do not conduct. Low densities Low melting points

Metalloids State of matter at room temperature –All solids Valence electrons –Varies Group Numbers –Follows the stair steps

Characteristics Conduct better than nonmetals, but not as good as metals. –AKA: semiconductors. They contain properties of both metals and nonmetals.

Group 1 – Alkali metals  __VE –Most reactive of metals –Exists as compounds, not elements –Lower metallic densities –Used in batteries, drugs, fertilizers

Group 2 – Alkaline Earth Metals  __ VE –Don’t occur free in nature –Mg only used on a large scale Used in fireworks and building materials –Ca VERY important to bones

Groups 3-12 – Transition metals –VE varies –Exists as elements in nature –High MP, BP and densities –VERY conductive –Uses: wires, pipes, cast iron, coloring glass and paint Cu, Fe, Cr, Co, Cd

Inner Transition Elements Lanthanides –Atomic #’s 57 – 71 –Rare earth metals –Uses: lamps, lasers, magnets, motion picture projectors, and X-ray intensifying screens. AKA: Synthetic Elements

Inner Transition Elements Actinides –Atomic #’s 89 – 103 –Actinides do not occur in nature –Radioactive –Tarnish readily –Very dense AKA: Synthetic Elements Elements 93 & above found only in laboratories.

Group17 – Halogens  ___ VE –Most reactive of the nonmetals! Same reactivity value as Alkali metals –Many uses Toothpaste, disinfectant, glass etching –Form salts

Group18 – Noble Gases  __ VE –Do not readily bond at all –No naturally occurring compounds exist. –Colored signs, light bulbs, windows, balloons

Mixed Groups Group 13 –Boron Group  ____ VE Group 14 –Carbon Group  ____VE Group 15 –Nitrogen Group  ____VE Group 16 –Oxygen Group  ____VE