Honors Chemistry - Periodic Table

Group/Family

Columns of elements, having similar but not identical properties

Period

Rows of elements, having different properties, but the same number of orbitals

Metal

• majority of elements

• good conductors of heat and electricity

• lustrous, ductile, malleable

• subject to corrosion

Luster

Shiny

Ductile

Can be stretched (into wires)

Malleable

Can be pounded into thin sheets

Corrosion

Reactive with acids or components of the environment that break down the element

Metalloid

• found along stair step

• properties are between metals and nonmetals

• shiny or dull

• semi-conductors

• ductile and malleable, or brittle

Nonmetal

• poor conductors of heat and electricity

• brittle and break easily

• dull, possible crystal shine

• many are gas

Actinide

• radioactive

• unstable nuclei

• metal

• tarnish in air

• can undergo nuclear reactions

Other/Post Transition Metal

• solid at room temp

• high melting point

• good conductors of heat and electricity

• shiny and ductile

Halogens

• 7 valence electrons

• high reactivity (most reactive nonmetal)

• typically found in nature

• found in p-block

• low boiling and melting point

• toxic

Noble Gases

• full outer electron shell (8 valence electrons)

• gases at room temp

• no color, smell, or taste

• unreactive/inert

• calm and independent

• found in small amounts in the atmosphere

What 4 elements did early philosophers believe existed?

Fire, Air, Water, Earth

Who is credited as the father of the modern periodic table?

Dmitri Mendeleev

How did Mendeleev organize the periodic table?

By atomic number

Who came after and related the number of protons to the atomic number and rearranged some of the elements?

Henry Moseley

How many naturally occurring elements are there?

90

How many synthetic elements are there?

28

Alkali Metal

• 1 valence electron

• most reactive to oxygen and water

• high boiling point, but low compared to others

• other metal characteristics

Alkaline Earth Metal

• 2 valence electrons

• reactive (other than beryllium)

• silver to white color

• metal characteristics

Transition Metal

• hard and lustrous

• high melting point

• good conductor of heat and electricity

How are elements now arranged on the periodic table? How else are they arranged?

By atomic number, then by properties and color as well

Lanthanide

• f-block

• rare earth metal

• all natural

• metal characteristics