The Periodic Table of Elements  1870 Dimitri Mendeleev  1 st orderly arrangement of elements  Not all elements fit in order  Left blanks were elements could be

IUPAC – most common version  Period – rows of increasing atomic mass  Group – columns of elements with similar properties  3 types of elements:  Metals – good conductors; most elements  Nonmetals – far right hand side  Semiconductors/metalloids – stair step in between; conductors some situations

The Main Groups of Elements “Representative Elements”

Metals, Nonmetals, Metalloids  Metals - conductors of electricity, luster, malleable, reactive, solids  Nonmetals - not conductors of electricity, reactive & non- reactive, gases, liquids and solids  Metalloids - semiconductors, solids

7 major groups of elements  Alkali metals  Alkaline Earth Metals  Transition Metals  Metalloids  Halogens  Nobel Gases  Lanthanide/Actinides

Alkali Metals  Group 1 Li, Na, K, Rb, Cs, Fr  Highly reactive with water, can burn in air  Soft, shiny gray

Alkaline Earth Metals  Group 2 Be, Mg, Ca, Sr, Ba, Ra Be, Mg, Ca, Sr, Ba, Ra  Harder, denser, stronger than alkali metals

Transition metals  Found in middle of chart  Place where “metals” are found

Metalloids  Have properties of metals and nonmetals  Aka: semiconductors  Used in computer chips, can “print” electric circuits  Ex: silicon/germanium

Halogens  Found in group 17 F, Cl, Br, I, As  Gases (Br liquid) and highly reactive  Like to react with metals from groups 1 & 2

Nobel Gases  Group 18 He, Ne, Ar, Kr, Xe, Rn  Inert gases - aren’t reactive with other elements

Lanthanides and Actinides  Found “pulled” out on the periodic chart  Used in TV, computers  Radioactive and used in nuclear energy plants and for bombs

Synthetic Elements  Produced in laboratory  Technetium and Promethium  Used in “xray” machines

LABEL THE PERIODIC TABLE: Alkali Metals Alkali Metals Alkaline Earth Metals Alkaline Earth Metals Halogens Halogens Noble Gases Noble Gases Semi-conductors Semi-conductors Transition metals Transition metals Lanthanides/Actinides Lanthanides/Actinides

Trends in the periodic table  Size of atoms  Increases from right to left  Increases as go down a group

Trends in the periodic table  Reactivity  More reactive on “edges” (except grp 18)  Left side – more reactive at bottom of group  Right side – more reactive at top of group

Arrange these atoms from smallest to largest  Sodium, chlorine, silicon, argon, magnesium  Phosphorus, antimony, nitrogen, bismuth

Arrange these atoms from most reactive to least reactive  Radium, calcium, beryllium, strontium, magnesium, barium  Iodine, astatine, fluorine, bromine, chlorine  Rubidium, ruthenium, calcium, selenium, chlorine, Xenon