Introduction To The Periodic Table Of The Elements October 26, 2009

Who Came Up With The Periodic Table Anyway? Dmitri Mendeleev  Came up with cards for each element  Put them on a wall in order of increasing atomic mass  It was like a game of cards, where Mendeleev tried arranging the elements in vertical columns and horizontal rows

The Periodic Table What three pieces of information does each square give?

Organizing The Elements Every element has a group and a period: Group – A group is a vertical column of elements on the periodic table of the elements Period – A period is a horizontal row of elements on the periodic table of the elements

Common Groups Alkali Metals Alkaline Earth Metals Halogens Noble Gases

Alkali Metals Group 1 React rapidly when exposed to air and water Ex:

Alkaline Earth Metals Group 2 Less reactive than alkali metals If heated, they will burn in air Ex:

Halogens Group 17 The most reactive non-metals Corrosive Ex:

Noble Gases Group 18 Inert Odourless, colourless gases at room temperature Ex:

Periodic Table Organizers Atomic Number – The atomic number is used to organize he elements within the periodic table of the elements Atomic Mass – The atomic mass is the average mass of an elements' atom Where will these concepts be important?

Atomic Notation Atomic notation allows for the atomic mass and atomic number of an element to be visible. He 4 2 Atomic Mass Atomic Number

Subatomic Particle Details Atomic number = number of protons = number of electrons (atoms have no overall electrical charge) Atomic mass - atomic number = number of neutrons

Subatomic Particle Example Ex: