Periodic TrendsPeriodic Trends

Periodic Table of the ElementsWhat does the staircase line separate?

The 3 major distinctions of the The 3 major distinctions of the Periodic TablePeriodic Table

1.1. MetalsMetals2.2. NonmetalsNonmetals3.3. MetalloidsMetalloids

Metals: Metals: To the left of the staircase line To the left of the staircase line

Physical PropertiesPhysical Properties:: Luster (shiny)Luster (shiny) Good conductorsGood conductors High densityHigh density High melting pointHigh melting point MalleableMalleable Ductile (draw into Ductile (draw into

wire)wire)

Chemical Chemical Properties:Properties:

Easily lose electronsEasily lose electrons Corrode easily (ex: Corrode easily (ex:

rusting or tarnishing)rusting or tarnishing)

Non metals: Non metals: to the right of the staircase lineto the right of the staircase line

Physical Properties:Physical Properties: DullDull Poor conductorPoor conductor BrittleBrittle Not malleableNot malleable Low density and Low density and

melting pointmelting point• Chemical Property:Chemical Property:

Tend to gain electronsTend to gain electrons

Metalloids: Metalloids: along the staircase linealong the staircase line

SolidsSolids Shiny or dullShiny or dull MalleableMalleable Conduct heat and Conduct heat and

electricity better than electricity better than non metal but not as non metal but not as well as metalswell as metals

Back to the Periodic Table…Back to the Periodic Table… The elements are arranged in order of The elements are arranged in order of

INCREASING atomic number (and atomic weight)INCREASING atomic number (and atomic weight) Another trend in the Periodic Table is the Another trend in the Periodic Table is the

arrangement of arrangement of Periods (horizontal rows)Periods (horizontal rows) and and Groups (vertical columns)Groups (vertical columns)

Group 1: Alkali MetalsGroup 1: Alkali Metals strong metals that are strong metals that are

unusually soft unusually soft very reactive toward very reactive toward

OxygenOxygen All of these metals All of these metals

have one valence have one valence electron and are thus electron and are thus very reactive very reactive

Group 2: Alkaline Earth MetalsGroup 2: Alkaline Earth Metals not as soft as Group 1 not as soft as Group 1

metals. metals. react more mildly with react more mildly with

OxygenOxygen These elements have These elements have

two valence electrons two valence electrons and form cationsand form cations

Transition MetalsTransition Metals These metals are not These metals are not

as predictable as as predictable as other metalsother metals

Wide variety of Wide variety of propertiesproperties

Groups 3-12 on Groups 3-12 on periodic tableperiodic table

Group 17 :Halogen Group 17 :Halogen

only need one only need one additional electron to additional electron to complete their outer complete their outer shells shells

““salt makers”salt makers” Ex: NaCl, where Cl is Ex: NaCl, where Cl is

a halogena halogen

Group 18 : Noble gasesGroup 18 : Noble gases Non-reactiveNon-reactive Stable electron Stable electron

formationformation Also known as “inert Also known as “inert

gases”gases”