The Periodic TableThe Periodic Table

Of ElementsOf Elements

Development of the Modern Development of the Modern Periodic TablePeriodic Table

ObjectivesObjectivesTrace the development and identify key Trace the development and identify key

features of the periodic tablefeatures of the periodic table Identify specific groups within the periodic Identify specific groups within the periodic

tabletable

Organizing by PropertiesOrganizing by Properties

1869 – Dmitri Mendeleev organized known 1869 – Dmitri Mendeleev organized known elements into chart (rows and columns)elements into chart (rows and columns)

According to atomic massAccording to atomic massSimilar to putting together a large puzzleSimilar to putting together a large puzzlePredicted new elements would be Predicted new elements would be

discovered with certain propertiesdiscovered with certain properties

Arranging by Atomic NumberArranging by Atomic Number

Many discrepancies with MendeleevMany discrepancies with Mendeleev’’s s tabletable

Moseley arranged by increasing atomic Moseley arranged by increasing atomic number rather than atomic massnumber rather than atomic mass

Discrepancies disappearedDiscrepancies disappeared

Periodic LawPeriodic Law

The properties of the elements repeat The properties of the elements repeat periodically when the elements are periodically when the elements are arranged in increasing order by their arranged in increasing order by their atomic number.atomic number.

Modern Periodic TableModern Periodic Table

First Ionization EnergyFirst Ionization Energy

The energy required to remove one The energy required to remove one electron from an atom in a gaseous phaseelectron from an atom in a gaseous phase

Periodic Table TodayPeriodic Table Today

Vertical column = group or familyVertical column = group or familyHorizontal row = periodHorizontal row = period

Check out periodic table on wallCheck out periodic table on wall

Chemical FamiliesChemical Families

1A = 1A = alkali metalsalkali metals (react with water to form (react with water to form alkaline, or basic, solutionalkaline, or basic, solution

2Na(s) + 2H2Na(s) + 2H22O(l) = 2NaOH(aq) + HO(l) = 2NaOH(aq) + H22(g) + heat (g) + heat energyenergy

2A = 2A = alkaline earth metalsalkaline earth metals also react with water also react with water 7A = 7A = halogenshalogens (salt formers)\ (salt formers)\ 1A-8A = 1A-8A = representative metalsrepresentative metals Bgroup (2A-3A) = Bgroup (2A-3A) = transition metalstransition metals Two bottom rows = Two bottom rows = inner transition metalsinner transition metals

(lanthanides and actinides)(lanthanides and actinides)

PeriodsPeriods

77thth period incomplete – fewer than half period incomplete – fewer than half occur naturally on earth and all are occur naturally on earth and all are radioactiveradioactive

Classification Cont.Classification Cont.

Metals – to the left of the staircaseMetals – to the left of the staircase Properties: generally shiny when smooth and clean, solid at Properties: generally shiny when smooth and clean, solid at

room temperature, good conductors of heat and electricityroom temperature, good conductors of heat and electricity

Nonmetals – to the right of the staircaseNonmetals – to the right of the staircase Properties: generally gases or brittle, dull-looking solids. Poor Properties: generally gases or brittle, dull-looking solids. Poor

conductors of heat and electricityconductors of heat and electricity

Metalloids – bordering staircaseMetalloids – bordering staircase Si and Ge are most important for use in semiconductorsSi and Ge are most important for use in semiconductors

HomeworkHomework

6.1 assessment6.1 assessmentP.174 # 26-40P.174 # 26-40

Quarter extra credit (25 points exam)Quarter extra credit (25 points exam)Develop a periodic table (must be large on Develop a periodic table (must be large on

posterboard) expressing periodicity in an posterboard) expressing periodicity in an interest you may haveinterest you may have

ActivityActivity

In the cards periodic table activityIn the cards periodic table activity