Periodic table

Periodic Table

First arranged by a a man named Demitry Mendeleev who arranged it by atomic mass.

One square has the following : the atomic number, atomic mass, the chemical symbol, and the chemical name.

It was then rearranged by Henrey Moseley in 1914, by atomic number; today we still order it by atomic number.

valence electron(s): the electron(s) in the most outer cloud; group numbers affect the number of valence electrons in the elements' outer most cloud ex. group 8 = 8 valence electrons

The Periodic Table is made up of three basic parts: metals, nonmetals, and metalloids (half-and-half).

All atoms want a full outside cloud. They will bond with other clouds/atoms to complete their clouds. They do so by gaining, losing, or sharing an electron with another atom, and they do whatever is easiest, or uses the least amount of energy.

group: vertical columns (18); have same properties as each other; same number of electrons in most outer electron cloud.

period: horizontal rows (7); have the same number of electron clouds.

Charlotte YePer. 1

Group 1 : Alkali metalsGroup 2 : Alkaline-earth metalsGroups 3-12 : Transition metalsGroups 13 : (Boron Group)Group 14 : (Carbon Group)Group 15 : (Nitrogen Group)Group 16 : (Oxygen Group)Group 17 : HalogensGroup 18 : Noble Gases

periodic: repeating; a repeated pattern

Metals (found on left side)-their most outer cloud is almost empty-malleable and ductile; shiny-good conductors of heat/electricityNonmetals (found on right side)-basically completely opposite of metals, for all characteristicsMetalloids (found on zigzag)-can act like either metal or nonmetal-their outer most cloud is half full-shiny or dull; semiconductors

ex. Group 1 : (far left)-Alkali metals- 1 valence electron-very reactive-low density