Chapter 19 Periodic table Notes

Periodic means repeating pattern Mendeleev was the first to arrange the elements in ascending order by atomic mass

The Modern Periodic table was organized by Henri Moseley He arranged the elements according to atomic number

Vertical columns on the periodic table are called groups or families There are 18 groups Elements in the same group have similar properties. They have the same valence ( outer number on energy levels) number

Horizontal rows on the periodic table are called periods There are 7 periods on the table Represent the number of energy levels for each element in that period

Metals are located on the left of the stair step line

Nonmetals are located on the right of the stair step line

Metalloids touch the stair step line Also called semi metals or semi conductors

Valence electrons- number of electrons in the outer energy level Each group has the same valence number

Metals Ductile.. Drawn into thin wires Malleable.. Hammered in to thin sheets Soft Luster.. Shiny Good conductors of electricity

nonmetals Not malleable Not ductile Not good conductors of electricity Brittle…. Break easily Dull… no shine

metalloids On the zig zag line Properties of both metals and nonmetals Semiconductors Semi-metals

Group 1 Alkali family Valence= 1 Most reactive metals Combine easily with group 17 All properties of metals Oxidation number 1

Group 2 Alkaline Metals Valence = 2 All metals Ox number 2

3-12 Transition Metals Includes the coinage metals: Ag, Cu, Au Valence = 2 or 3 or 4.. Depends on bond

Group 13 Boron Family Valence = 3 Metalloids and metals Aluminum is sometimes called a metal Ox. Number 3

Group 14 Carbon Family Valence 4 Metals, nonmetals, metalloids Ox number 4

Group 15 Nitrogen Group Valence = 5 Nonmetals, metalloids and metals Ox number 3

Group 16 Oxygen Family Valence = 6 Nonmetals and metalloids Polonium is radioactive Ox number 2

Group 17 Halogens Valence = 7 Combines easily with group 1 Nonmetals and one metalloid Ox number -1

Group 18 Noble Gas Also known as the Inert Gas Family “inert” means lazy Do not combine with any other group Valence 8 All gases, nonmetals and lightweight Very stable

Valence electrons- number of electrons in the outer energy

Lanthanide Series 1st row of the Rare Earth Elements 57-71 All metals

Actinide Series 2nd row of the Rare Earth Elements 89-103 Many radioactive elements: plutonium, uranium, thallium Most are synthetic elements All metals

Vocabulary Synthetic- man made Oxidation number - number of electrons an atom will gain, lose or share to reach the magic number 8 Radioactive- decaying of the nucleus that releases energy