The Periodic TableThe Periodic Table

Early OrganizationEarly Organization As early as the early Greeks, As early as the early Greeks,

scientists wanted to organize.scientists wanted to organize. They separated matter into Earth, Air, They separated matter into Earth, Air,

Fire and Water. Fire and Water. They even had more detail such as They even had more detail such as

combinations.combinations. For example: Earth and Fire = LavaFor example: Earth and Fire = Lava Check out the game Little Alchemy Check out the game Little Alchemy

on GOOGLE – you might like it.on GOOGLE – you might like it.

History of the Periodic Table History of the Periodic Table

In the 1700s In the 1700s scientists had scientists had identified only identified only 30 elements30 elements

In the 1800s In the 1800s there were 60there were 60

History of the Periodic Table History of the Periodic Table

Early 1800s Early 1800s Dobereiner Dobereiner grouped elements grouped elements into triadsinto triads

Li, Na, KLi, Na, K

History of the Periodic Table History of the Periodic Table 1865 J.A.R. Newlands 1865 J.A.R. Newlands

discovered properties discovered properties repeated themselves repeated themselves every eighth element every eighth element

Called these octavesCalled these octaves

Mendeleev Mendeleev 1869 Dmitri Mendeleev 1869 Dmitri Mendeleev

produced the first produced the first periodic table for his periodic table for his studentsstudents

Left blanks where Left blanks where elements had yet to be elements had yet to be discovereddiscovered

Was organized by Was organized by atomic weight as that atomic weight as that was the standard at was the standard at the time.the time.

Here is one of the early official versions of Mendeleev’s Periodic Chart

Notice it is in German, even though Mendeleev was Russian.

Properties of Germanium as Predicted by MendeleevProperties of Ekasilicon Predicted in 1871

Atomic weightDensity  

Specific heatMelting pointOxide formula  

Oxide density  

Chloride formula  

bp of chloride

725.5 g/cm3

0.31 J/(°C · g)Very highRO2

4.7 g/cm3

RCl4100°C

Properties ofGermanium

Predictedin 1871

Observed  in1886

Atomic weightDensity  

Specific heatMelting pointOxide formula  

Oxide density  

Cl-1 formula  

bp of chloride

725.5 g/cm3

0.31 J/(°C · g)

Very highRO2

4.7 g/cm3

RCl4100°C

72.35.47 g/cm3

0.32 J/(°C · g)

960°CGeO2

4.70 g/cm3

GeCl486°C

HenryMoseleyHenryMoseley

In 1913 Moseley In 1913 Moseley assigned elements assigned elements atomic numbers and atomic numbers and rearranged periodic rearranged periodic table.table.

Table TermsTable Terms

Periodic LawPeriodic Law – when arranged by – when arranged by increasing atomic number increasing atomic number elements repeat similar chemical elements repeat similar chemical and physical propertiesand physical properties

Groups or Families Groups or Families are the are the columns on the periodic tablecolumns on the periodic table

Periods Periods are the rows going across.are the rows going across.

Major Groups on the Periodic Major Groups on the Periodic TableTable

Alkali MetalsAlkali Metals Alkaline Earth Alkaline Earth

MetalsMetals Transition Transition

Metals Metals Boron GroupBoron Group Carbon GroupCarbon Group Nitrogen GroupNitrogen Group

Oxygen Group Oxygen Group (Chalcogens)(Chalcogens)

HalogensHalogens Noble GasesNoble Gases Actinide SeriesActinide Series Lanthanide Lanthanide

SeriesSeries

Metals, Nonmetals, and Metals, Nonmetals, and MetalloidsMetalloids

6.1

Check out Theodore Gray’s App – The elements

Metals, Nonmetals, and Metals, Nonmetals, and MetalloidsMetalloids

6.1

Metals, Nonmetals, and Metals, Nonmetals, and MetalloidsMetalloids

Metals, Metalloids, and Nonmetals in the Periodic TableMetals, Metalloids, and Nonmetals in the Periodic Table

6.1

Metals, Nonmetals, and Metals, Nonmetals, and MetalloidsMetalloids

Metals, Metalloids, and Nonmetals in the Periodic TableMetals, Metalloids, and Nonmetals in the Periodic Table

6.1

Metals, Nonmetals, and Metals, Nonmetals, and MetalloidsMetalloids

6.1

MetalsMetals Good Conductors of Good Conductors of

heat and electricityheat and electricity Luster – ShinyLuster – Shiny Malleable – pounded Malleable – pounded

into thin sheetsinto thin sheets Ductile – pulled into Ductile – pulled into

a wirea wire Mercury is the only Mercury is the only

liquid metal at room liquid metal at room temptemp

Non-MetalsNon-Metals

Most are gasesMost are gases Solids are brittle Solids are brittle

(S & P)(S & P) Bromine is the Bromine is the

only liquid only liquid nonmetal at room nonmetal at room temptemp

MetalloidsMetalloids

Properties of Properties of metals and non-metals and non-metalsmetals

Semi conductorsSemi conductors Make very good Make very good

computer chipscomputer chips

Atomic RadiusAtomic Radius

Atomic radiusAtomic radius is the distance from the is the distance from the atom’s nucleus to its outer edge.atom’s nucleus to its outer edge.– In the same energy level, more In the same energy level, more

protons exert a stronger pull towards protons exert a stronger pull towards the nucleusthe nucleus

Showing the Trend of Atomic SizeShowing the Trend of Atomic Size

Which has larger atomic Which has larger atomic radius?radius?

Na or RbNa or Rb P or ClP or Cl

You can tell by looking You can tell by looking at the chart and at the chart and knowing the trend.knowing the trend.

Ionization EnergyIonization Energy Ionization energy Ionization energy is the energy is the energy

needed to remove one electronneeded to remove one electron Na Na ((gg)) Na Na+1 +1 ((gg)) + 1 e + 1 e-1-1 Metals are more likely to give up an Metals are more likely to give up an

electron than nonmetals.electron than nonmetals.

Trends in Ionization EnergyTrends in Ionization Energy

It is good to know that Fluorine has the highest Ionization Energy

Which has larger ionization Which has larger ionization energy?energy?

H or CsH or Cs Li or NLi or N

Ionic RadiusIonic Radius Ionic radiusIonic radius is the distance from is the distance from

the ion’s nucleus to its outer the ion’s nucleus to its outer edge.edge.

Non-metal ions get larger with a Non-metal ions get larger with a negative chargenegative charge

Metal ions get smaller with a Metal ions get smaller with a positive chargepositive charge

This is because more protons are This is because more protons are pulling on fewer electronspulling on fewer electrons

Anions are going to be larger than the atom. Cations are going to be smaller than the atom.

Trends in Ionic SizeTrends in Ionic Size

Relative Sizes of Some Atoms and IonsRelative Sizes of Some Atoms and Ions

Which of the following is Which of the following is larger?larger?

O or OO or O-2-2

K or KK or K++

Any Questions???? Any Questions????

ElectronegativityElectronegativity

Electronegativity Electronegativity reflects an reflects an atom’s ability to attract electronsatom’s ability to attract electrons

Cs & Fr have the lowest Cs & Fr have the lowest electronegativities; F has the electronegativities; F has the highesthighest

Reactivity of Alkali and Alkaline Reactivity of Alkali and Alkaline Earth MetalsEarth Metals

Metals become Metals become more reactive as more reactive as you move down you move down the groupthe group

Metals become Metals become less active when less active when moving left to moving left to rightright

Why Are There Patterns ?Why Are There Patterns ? Elements have physical and Elements have physical and

chemical properties based upon chemical properties based upon their valence electrons.their valence electrons.

Valence electronsValence electrons are the are the electrons in the outer most energy electrons in the outer most energy level (s & p orbitals).level (s & p orbitals).

The number of valence electrons The number of valence electrons may be determined by using the may be determined by using the periodic table.periodic table.

Why Are There Patterns?Why Are There Patterns? When you look at an atom you are When you look at an atom you are

observing the valence electronsobserving the valence electrons Duet rule - only 2 electrons fill the Duet rule - only 2 electrons fill the

first energy levelfirst energy level Octet rule – 8 valence electrons is Octet rule – 8 valence electrons is

considered to be a full setconsidered to be a full set

Electron AffinityElectron Affinity Electron affinity Electron affinity is the energy change that is the energy change that

occurs when an atom gains an electron.occurs when an atom gains an electron. F F ((gg)) + e + e-1-1 F F-1-1 ((gg)) Most atoms give off energy when an electron Most atoms give off energy when an electron

is gained (negative).is gained (negative). Nonmetals have more of an electron affinity Nonmetals have more of an electron affinity

than metals.than metals. EA decreases when moving down the group.EA decreases when moving down the group. EA increases moving from left to right in a EA increases moving from left to right in a

period.period.