Periodic Table

Periodic Table

Jennifer ThompsonP.6

In the 1860's a man by the name of Mendeleev created the periodic table and he organized it by their atomic mass.

In 1914 another scientist named Moseley came along and rearranged the periodic table by the elements atomic number.

There are 3 classes of elements on the periodic table.

Metals -located on the left side of the periodic table- their outer cluds are almost empty-good conductors of heat and electricity

Non Metals-located on the right side of the periodic table- their outer cloud is almost full- not shiny- poor conductors

Metaloids-surrounds the zig zag line on the periodic table- somethimes can act as a metal and sometimes it can act as a non metal- cam be shiny or dull- their outer clouds are half full- semi - conductors

Group 1-alkali metals- one outer electrons-very reactive!-low density

Group 2- alkaline earth metals- has 2 outer clouds- verry reactive but not as much as group 1

Gropups 13-16- named by the top element of its groups- kind of reactive- to find the valence electron just subtract 10 from - includes metaloids-located towards the right side of the periodic table.

Groups 3-12- transition metals- all metals have 1 or 2 electrons- less reactive than 1 and 2- shiny and good conductors- higher densities and melting points.- 2 extra rows on the bottom of the periodic table.

Group 17- non metals - halogen group- 7 outer electrons- verry reactive-forms salt.

Group 18- noble gasses- 8 outer electrons- unreactive- the outer cloud is full

Hydrogen- one outer electron- very reactive- it does not match any other group s it is placed by itself- belong on th eright and left side -right:because non metal-left: has one outer electron

Period is the horizontal columns on the periodic table.

Groups is the vertical columns on the periodic table.