Quick Question: Who developed the Periodic Table of Elements? What property was the original Periodic Table of Elements arranged according to? How many elements were there when the table was developed? Why were there spaces or gaps in the table? What property is the Periodic Table arranged according to in modern times?

Today’s Objective: I understand the arrangement of the Periodic Table of Elements and can use it describe and predict the properties of elements.

Periodic table Mendeleev’s chart was renamed the periodic table Is an arrangement of elements in columns, based on a set of properties that repeat from row to row

Mendeleev didn’t know about atoms All atoms of element have same number of protons Atoms of two different elements could not have the same number of protons

Modern Periodic table Elements are arranged by increasing atomic number (number of protons)

The actinides and lanthanides are below the table to emphasize their similarities related to their electron configuration

Modern periodic table Periods are the horizontal rows There are 7 Period # tells the # of energy levels (shells) for those elements

Groups/Families Vertical columns There are 18 Elements within a group have similar chemical properties Pattern of repeating is known as periodic law

A groups For the 8 “a’” groups, the group # is the # of valence (outer shell) electrons

Modern periodic table Four pieces of info for each element Name of element Symbol Atomic number Atomic mass

Atomic mass A value that depends on the distribution of an element’s isotopes in nature and the masses of those isotopes An atomic mass unit (amu) is defined as one twelfth the mass of a carbon-12 atom

General Properties of elements on periodic table Solids, liquids, gases Majority are solids 2 liquids: Hg (Mercury), Br (Bromine) 11 Gases: h, he, N, o, f, cl, ne, ar, kr, xe, rn

General properties of Elements Naturally occurring All but 2 elements with atomic #s 1 – 92 occur naturally Those not found in nature Synthetic Atomic # 93 and higher

General properties of elements Metals, Mettalliods, Nonmetals

Metals Good conductors of heat and electricity Solids (except mercury) Ductile-ability to be drawn into wires Malleable-ability to be hammered into sheets Shiny To the left of stairs are metals (except H) As you go from top to bottom metallic properties increase

Lanthanide Series – 57-70 Belong to row 6 Actinide Series – 89-102 Belong to row 7

Outline all of the Metals in Black

Transition metals are located in groups 3-12 (AKA B groups)

Transition metals Form a bridge between the elements on the left and those on the right Form compounds with distinctive colors

Color the Transition metals dark green DON’T COLOR THE ELEMENTS THAT ARE BLACKED OUT! THEY ARE NOT METALS! WE ONLY WANT TO COLOR METALS!!! Become more Metallic

Color the inner transition (lanthanide & actinide) metals light green DON’T COLOR THE ELEMENTS THAT ARE BLACKED OUT! THEY ARE NOT METALS! WE ONLY WANT TO COLOR METALS!!! Become more Metallic

Metalloids Elements with properties that fall between those of metals and nonmetals All touch stairs Except Al, it is a metal Metalloids ability to conduct electric current varies with temp Pure silicon and germanium good insulators at low temp good conductors at high temp

Outline all of the Metalloids in Green

Nonmetals Poor conductors of heat and electricity Low boiling points, so most are gases at room temp Solids at room temp are brittle Fluorine is most reactive nonmetal To the right of stairs As you go from bottom to top the nonmetallic properties increase

Outline the nonmetals!! Become more NonMetallic

Think fast!!! What does the period # tell you? # of energy levels What does the A group # tell you? # of valence electrons How many periods on periodic table? 7 Other names for groups? Columns, families

Periodic table Why is hydrogen located on the left side with group 1-active metals……shouldn’t it be with the other gases in group 17? Hydrogen’s location is based on it’s electron configuration (Valence Electrons)…..not it’s properties

Valence Electrons (aka the outer shell electrons!!) Is an electron in the highest occupied energy level of an atom Key role in chemical reactions Elements in a group have similar properties bc they have the same number of valence electrons For the “a” groups, the group number tells how many valence electrons there are

Alkali metals Group 1A One valence/outer shell electron Extremely reactive Reactivity increases as you go down the column Francium is the most reactive Label on reference table

Color the Alkali Metals Red

Alkaline Earth metals Group 2a Two valence e- HARDER THAN METALS IN GROUP 1A REACTIVIY IS SHOWN BY THE WAY EACH ELEMENT REACTS W/ WATER Label on reference table

Color the Alkali Earth Metals Blue

The Boron Family Group 3a 3 valence e- ALUMINUM IS THE MOST ABUNDANT METAL IN EARTH’S CRUST!!!

Color the Boron Family Brown

The Carbon Family Group 4a 4 valence e- MOST OF Compounds IN YOUR BODY CONTAIN CARBON!! Silicon is the 2nd most abundant element in Earth’s crust! Label on reference table

Color the Carbon Group Purple

The Nitrogen Family Group 5a 5 valence e- Nitrogen & Phosphorus are used in fertilizers Bodies-control reaction & release energy from food

Color the Nitrogen Group Pink

The Oxygen Family Group 6A 6 valence e- Oxygen is most abundant element in the Earth’s crust

Color the Oxygen Group Light Blue

The halogen group Group 7A 7 valence e- Chemical properties Label on reference table Group 7A 7 valence e- Chemical properties Highly reactive (fluorine is the most reactive nonmetal) Reactivity increases from bottom to top

Color the Halogens Orange

The noble gases Group 8A 8 valence e- (EXCEPT He –IT ONLY HAS 2) Colorless, odorless, & EXTREAMELY UNREACTIVE!! “stable elements

Color the Noble Gases Yellow

Think Fast!!! Most reactive nonmetal? Fluorine Most Reactive metal? Francium What is special about Helium Only 2 valence e- DESCRIBE THE NOBLE GASES? STABLE, UNREACTIVE, ODORLESS, COLORLESS