groups in the periodic table

• metals

  • conductors (to varying degrees)

  • lose electrons

  • malleable and ductile (flexible)

  • shiny/lustrous

• nonmetals

  • nonconductors

  • gain electrons

  • brittle (not malleable or ductile)

  • dull in texture/appearance

• metalloids/semi-conductors

  • bridge metals and non-metals, have qualities of both

metal groups

• alkali metals

  • have one valence electron (electron in the highest occupied energy level)

  • most reactive metal group

• alkaline earth metals

  • 2 valence electrons

  • less reactive than alkali metals

  • 2nd most reactive group

• transition metals

  • multiple charges on ions

  • some references refer to these elements as “post-transition metals”

  • don’t behave consistently

nonmetal groups

• halogens

  • 7 valence electrons

  • most reactive nonmetal group

• noble gases

  • 8 valence electrons (highest occupied energy level is full)

  • most stable group

the periodic table

• periodic table: a systematic organization of the elements

• elements are arranged in order of atomic number

• the rows of the periodic table (left to right) are called periods

• the columns of the periodic table (top to bottom) are called groups or families

• elements in the same group have similar properties

• periodicity

• periodic = cyclical

• there is a repeating pattern of reactivities and other properties as we move across the periodic table

• metals are on the left side of the periodic table, whereas non-metals are on the right side of the table (except for Hydrogen). metalloids are near the right side but not on the far right.