Exploring the Periodic TableExploring the Periodic TableModern Chemistry; Holt, Rinehart, & WinstonModern Chemistry; Holt, Rinehart, & Winston

CHAPTER 5 – SECTION 1HISTORY OF THE PERIODIC TABLECHAPTER 5 – SECTION 1HISTORY OF THE PERIODIC TABLEIn the late 1800s, scientists had identified over 60 elements. Certain characteristic physical and chemical properties were associated with each element. The physical property called atomic mass provided chemists with a convenient way to organize the elements. At the same time, it was recognized that there were certain elements that had similar chemical properties. Mendeleev arranged the elements in rows according to atomic weight and kept elements with similar chemical properties in the same columns. Today elements are ordered according to atomic number rather than atomic mass.

In the late 1800s, scientists had identified over 60 elements. Certain characteristic physical and chemical properties were associated with each element. The physical property called atomic mass provided chemists with a convenient way to organize the elements. At the same time, it was recognized that there were certain elements that had similar chemical properties. Mendeleev arranged the elements in rows according to atomic weight and kept elements with similar chemical properties in the same columns. Today elements are ordered according to atomic number rather than atomic mass.

Learning Targets Learning Targets

I can explain the roles of Mendeleev and Moseley in the development of the periodic table.

I can describe the modern periodic table. I can explain how the periodic law can

be used to predict the physical and chemical properties of elements.

I can describe how the elements belonging to a group of the periodic. table are interrelated in terms of atomic number.

I can explain the roles of Mendeleev and Moseley in the development of the periodic table.

I can describe the modern periodic table. I can explain how the periodic law can

be used to predict the physical and chemical properties of elements.

I can describe how the elements belonging to a group of the periodic. table are interrelated in terms of atomic number.

Stanislao Cannizzaro (1826-1910)Stanislao Cannizzaro (1826-1910)

Italian chemist Determined a method

for accurately measuring the relative masses of atoms

His method allowed chemists to search for a relationship between atomic mass and other properties of elements

Italian chemist Determined a method

for accurately measuring the relative masses of atoms

His method allowed chemists to search for a relationship between atomic mass and other properties of elements

Russian chemist Credited as being the creator

of the first version of the periodic table of elements

Arranged his periodic table according to atomic mass so that elements with similar properties were in the same group

Some elements could not be arranged according to atomic mass in order to keep the elements arranged according to properties

Predicted the properties of elements that had not yet been discovered using his periodic table

Russian chemist Credited as being the creator

of the first version of the periodic table of elements

Arranged his periodic table according to atomic mass so that elements with similar properties were in the same group

Some elements could not be arranged according to atomic mass in order to keep the elements arranged according to properties

Predicted the properties of elements that had not yet been discovered using his periodic table

Dmitri Mendeleev (1834-1907)Dmitri Mendeleev (1834-1907)

Mendeleev’s Periodic Table Mendeleev’s Periodic Table “I began to look about and write down the elements with their atomic weights and typical properties, analogous elements and like atomic weights on separate cards, and this soon convinced me that the

properties of elements are in periodic dependence upon their atomic weights.” --Mendeleev, Principles of Chemistry, 1905, Vol. II

“I began to look about and write down the elements with their atomic weights and typical properties, analogous elements and like atomic weights on separate cards, and this soon convinced me that the

properties of elements are in periodic dependence upon their atomic weights.” --Mendeleev, Principles of Chemistry, 1905, Vol. II

English chemist Worked with Rutherford Proved Mendeleev’s

arrangement of the periodic table to be correct – only, the periodic table was arranged according to atomic number, not atomic mass

English chemist Worked with Rutherford Proved Mendeleev’s

arrangement of the periodic table to be correct – only, the periodic table was arranged according to atomic number, not atomic mass

Henry Moseley (1887-1915)Henry Moseley (1887-1915)

The Periodic LawThe Periodic Law

States that when elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic pattern

States that when elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic pattern

CHAPTER 5 – SECTION 2ELECTRON CONFIGURATION AND THE PERIODIC TABLE

CHAPTER 5 – SECTION 2ELECTRON CONFIGURATION AND THE PERIODIC TABLEThe modern periodic table has 112 squares, which represent a unique element. The distinctive shape of the periodic table comes in part from the periodic law. Elements in the same column have similar properties. These columns are referred to as groups or families of elements. The horizontal rows of the periodic table are called periods. The elements in the periodic table are also grouped as metals, nonmetals, and semimetals. Metals make up most of the periodic table and are located in the center and at the left of the table. With the exception of hydrogen, nonmetals are on the right side, and semimetals are located between the metals and nonmetals. The periodic table can also be viewed in terms of orbital blocks. These orbital blocks refer to the orbitals (s, p, d, and f ) which contain the elements’ incompleted sublevels of electrons.

The modern periodic table has 112 squares, which represent a unique element. The distinctive shape of the periodic table comes in part from the periodic law. Elements in the same column have similar properties. These columns are referred to as groups or families of elements. The horizontal rows of the periodic table are called periods. The elements in the periodic table are also grouped as metals, nonmetals, and semimetals. Metals make up most of the periodic table and are located in the center and at the left of the table. With the exception of hydrogen, nonmetals are on the right side, and semimetals are located between the metals and nonmetals. The periodic table can also be viewed in terms of orbital blocks. These orbital blocks refer to the orbitals (s, p, d, and f ) which contain the elements’ incompleted sublevels of electrons.

Learning Targets Learning Targets

I can describe the relationship between electrons in sublevels and the length of each period of the periodic table

I can locate and name the four blocks of the periodic table and explain the reasons for these names

I can discuss the relationship between group configurations and group numbers

I can describe the locations in the periodic table and the general properties of the alkali metals, the alkaline-earth metals, the halogens, the transition metals, the noble gases, the actinides, the lanthanides, the metals, the nonmetals, the metalloids, and the main group elements

I can describe the relationship between electrons in sublevels and the length of each period of the periodic table

I can locate and name the four blocks of the periodic table and explain the reasons for these names

I can discuss the relationship between group configurations and group numbers

I can describe the locations in the periodic table and the general properties of the alkali metals, the alkaline-earth metals, the halogens, the transition metals, the noble gases, the actinides, the lanthanides, the metals, the nonmetals, the metalloids, and the main group elements

Periodic Law Demonstrated in Groups Periodic Law Demonstrated in Groups

Why do elements in groups have similar physical and chemical properties?

Why do elements in groups have similar physical and chemical properties?

They have the same number of valence electrons in their outer energy levels.

Generally, the configurations of the outermost electron shells of elements within the same group are the same.

They have the same number of valence electrons in their outer energy levels.

Generally, the configurations of the outermost electron shells of elements within the same group are the same.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

METALSMETALLOIDSNONMETALS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

ALKALI METALS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

ALKALINE-EARTH

METALS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

HALOGENS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

NOBLE GASES

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

TRANSITION METALS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

INNER TRANSITION (Rare Earth)

METALS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

LANTHANIDES

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

ACTINIDES

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

PERIODS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

GROUPS

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

In the periodic table below, indicate the location of the groups, periods, alkali metals, alkaline earth metals, halogens, noble gases, lanthanides, actinides, transition metals, inner transition metals, main group elements, metals, nonmetals and metalloids.

MAIN GROUP ELEMENTS

Let’s Compare!Let’s Compare!

MetalsMetals Good

conductors of heat and electricity

Malleable Ductile Luster Typically

solids at room temperature

Good conductors of heat and electricity

Malleable Ductile Luster Typically

solids at room temperature

NonmetalsNonmetals Solids, liquids

and gases at room temperature

Solids are brittle and dull

Poor conductors of heat and electricity

Solids, liquids and gases at room temperature

Solids are brittle and dull

Poor conductors of heat and electricity

MetalloidsMetalloids Have properties

of both metals and nonmetals

Mostly brittle solids

Intermediate conductors of electricity- AKA semiconductors

Have properties of both metals and nonmetals

Mostly brittle solids

Intermediate conductors of electricity- AKA semiconductors

Properties of Alkali MetalsProperties of Alkali Metals

Extremely reactiveReadily react with water

and air Silvery in appearance Soft enough to cut with a

knife Lower densities than other

metals Lower melting points than

other metals

Extremely reactiveReadily react with water

and air Silvery in appearance Soft enough to cut with a

knife Lower densities than other

metals Lower melting points than

other metals

Properties of Alkaline-Earth MetalsProperties of Alkaline-Earth Metals

Harder & stronger than alkali metals

Higher densities & melting points than alkali metals

Less reactive than alkali metals

Harder & stronger than alkali metals

Higher densities & melting points than alkali metals

Less reactive than alkali metals

Properties of HalogensProperties of Halogens

Most reactive nonmetals

React readily with most metals to form salts

Most electronegative elements

Most reactive nonmetals

React readily with most metals to form salts

Most electronegative elements

Properties of Noble GasesProperties of Noble Gases

Least reactive elements because their highest occupied energy levels are completely filled with an octet of electrons (except He, which only requires 2 electrons to be filled).

Least reactive elements because their highest occupied energy levels are completely filled with an octet of electrons (except He, which only requires 2 electrons to be filled).

Properties of Transition MetalsProperties of Transition Metals

High densitiesHigh melting pointsGood conductors of

heat & electricityHigh lusterLess reactive than

alkali and alkaline-earth metals

High densitiesHigh melting pointsGood conductors of

heat & electricityHigh lusterLess reactive than

alkali and alkaline-earth metals

Properties of p Block MetalsProperties of p Block Metals

Harder and more dense than the s block metals

Softer and less dense than the d block metals.

Harder and more dense than the s block metals

Softer and less dense than the d block metals.

Properties of LanthanidesProperties of Lanthanides

Soft, silvery metalsSimilar reactivity to alkaline-earth

metals

Soft, silvery metalsSimilar reactivity to alkaline-earth

metals

Properties of ActinidesProperties of Actinides

All radioactiveThe first 4 have been found

naturally on Earth

All radioactiveThe first 4 have been found

naturally on Earth

Did you know?Did you know?

Oxygen, carbon, hydrogen and nitrogen make up 96% of the human body mass

Calcium and phosphorous make up 3%

Sodium, potassium, chloride and magnesium make up 0.7%

Iron, cobalt, copper, zinc, selenium, cyanide and fluorine are found in trace amounts

Oxygen, carbon, hydrogen and nitrogen make up 96% of the human body mass

Calcium and phosphorous make up 3%

Sodium, potassium, chloride and magnesium make up 0.7%

Iron, cobalt, copper, zinc, selenium, cyanide and fluorine are found in trace amounts

CHAPTER 5 – SECTION 3ELECTRON CONFIGURATIONS AND PERIODIC PROPERTIES

CHAPTER 5 – SECTION 3ELECTRON CONFIGURATIONS AND PERIODIC PROPERTIESMany of the properties of the elements change in predictable ways as you move across a period or move down a group of the periodic table. The predictable changes in these properties are called periodic trends. There are periodic trends for properties such as atomic radius, ionic size, ionization energy, electron affinity, and electronegativity. Knowledge of these trends helps develop a better understanding of the periodic table and of the patterns of behavior of the elements.

Many of the properties of the elements change in predictable ways as you move across a period or move down a group of the periodic table. The predictable changes in these properties are called periodic trends. There are periodic trends for properties such as atomic radius, ionic size, ionization energy, electron affinity, and electronegativity. Knowledge of these trends helps develop a better understanding of the periodic table and of the patterns of behavior of the elements.

Learning Targets Learning Targets

I can define the term periodic trend. I can define atomic radius, ionic radius,

ionization energy, electron affinity and electronegativity.

I can describe the general trends on the periodic table for atomic radius, ionic radius, electron affinity, ionization energy and electronegativity.

I can apply the trends on the periodic table to answer questions regarding size, electron affinity, ionization energy and electronegativity.

I can define the term periodic trend. I can define atomic radius, ionic radius,

ionization energy, electron affinity and electronegativity.

I can describe the general trends on the periodic table for atomic radius, ionic radius, electron affinity, ionization energy and electronegativity.

I can apply the trends on the periodic table to answer questions regarding size, electron affinity, ionization energy and electronegativity.

Atomic RadiiAtomic Radii

Atomic radius – one-half the distance between the nuclei of identical atoms that are bonded together

Atomic radius – one-half the distance between the nuclei of identical atoms that are bonded together

Distance between nuclei

Atomic Radius

Period TrendsPeriod Trends

Decreases across a periodDecreases across a period

Why?Why?

Protons are added to the nucleus moving across a period from left to right

This increases the charge of the nucleus (effective nuclear charge – Zeff)

As Zeff increases, the electrons are pulled closer to the nucleus

Protons are added to the nucleus moving across a period from left to right

This increases the charge of the nucleus (effective nuclear charge – Zeff)

As Zeff increases, the electrons are pulled closer to the nucleus

Period TrendsPeriod Trends

++ ++ + ++ + + +

Group TrendsGroup Trends

Increase down a group Increase down a group

Why?Why?

The addition of shells increases the electrons’ distance from the nucleus and the size of the atom

The addition of shells increases the electrons’ distance from the nucleus and the size of the atom

n=3

n=2

n=1

Electron-electron repulsion “plumps” up the atom

Zeff decreases the further the electrons are from the nucleus

Electron-electron repulsion “plumps” up the atom

Zeff decreases the further the electrons are from the nucleus

Variations in Atomic RadiiVariations in Atomic Radii

Atomic Radii TrendsAtomic Radii TrendsDECREASES

DE

CR

EA

SE

S

Ionization EnergyIonization Energy

The energy required to remove one electron from a neutral atom of an element creating an ion

A + Energy A+ + e-

The energy required to remove one electron from a neutral atom of an element creating an ion

A + Energy A+ + e-

Period TrendsPeriod Trends

Increase across a periodWhy?

Increase across a periodWhy?Zeff increases across the periodZeff increases across the period

Group TrendsGroup Trends

Decrease down the groupWhy?

Decrease down the groupWhy?Electron shielding causes a

decrease in effective nuclear charge

Electron-electron repulsion forces increase

Electron shielding causes a decrease in effective nuclear charge

Electron-electron repulsion forces increase

Draw the orbital notation for Group 5A and Group 6A.Can you explain the dips in the chart for these 2 groups?

Variations in Ionization Energies

Variations in Ionization Energies

If removing an electron will create an empty or ½ filled subshell, ionization energy will decrease.

Variations in Ionization Energies

Variations in Ionization Energies

Successive Ionization Energies

Successive Ionization Energies

Each successive electron removed from an ion feels an increasingly stronger effective nuclear charge (Zeff) – therefore, successive ionization energies are larger than 1st ionization energies

A large jump in ionization energy occurs when removing an electron from an ion that assumes a noble gas configuration

Each successive electron removed from an ion feels an increasingly stronger effective nuclear charge (Zeff) – therefore, successive ionization energies are larger than 1st ionization energies

A large jump in ionization energy occurs when removing an electron from an ion that assumes a noble gas configuration

Ionization Energy TrendsIonization Energy TrendsINCREASES

INC

RE

AS

ES

Electron AffinityElectron Affinity

The change in energy that a neutral atom undergoes when an electron is acquired (the ability to attract an e -)

A + e- A- + energy[negative energy value (exothermic)]

A + e- + energy A- [positive energy value (endothermic)]

The change in energy that a neutral atom undergoes when an electron is acquired (the ability to attract an e -)

A + e- A- + energy[negative energy value (exothermic)]

A + e- + energy A- [positive energy value (endothermic)]

Period TrendsPeriod Trends

Increase across a periodWhy?

Increase across a periodWhy?Zeff increases across the periodZeff increases across the period

Group TrendsGroup Trends

Decrease down the groupWhy?

Decrease down the groupWhy?Electron shielding causes a

decrease in effective nuclear charge

Electron-electron repulsion forces increase

Electron shielding causes a decrease in effective nuclear charge

Electron-electron repulsion forces increase

Variations in Electron Affinities

Variations in Electron Affinities

INCREASES

INC

RE

AS

ES

Electron Affinity TrendsElectron Affinity Trends

++

+

+

+

+

+

Ionic RadiiIonic Radii

Cation – positively charged ionCations are smaller than their parent atom – why?

Anion – negatively charged ionAnions are bigger than their parent atom – why?

Cation – positively charged ionCations are smaller than their parent atom – why?

Anion – negatively charged ionAnions are bigger than their parent atom – why?

Removal of an electron creates an unbalanced positive charge increasing Zeff and decreasing the radius of the ion.

Addition of an electron creates an unbalanced negative charge decreasing Zeff and increasing the radius of the ion.

Ionic Radii TrendsIonic Radii TrendsDECREASES

DE

CR

EA

SE

S

Valence ElectronsValence Electrons

Electrons available to be gained, lost or shared in the formation of a chemical compound

Located in the outer energy level

Electrons available to be gained, lost or shared in the formation of a chemical compound

Located in the outer energy level

ElectronegativityElectronegativity

A measure of the ability of an atom in a chemical compound to attract a bonding pair of electrons

NOTE *Electronegativity is a property of atoms in compounds and thus differs from ionization energy and electron affinity, which are properties of isolated atoms*

A measure of the ability of an atom in a chemical compound to attract a bonding pair of electrons

NOTE *Electronegativity is a property of atoms in compounds and thus differs from ionization energy and electron affinity, which are properties of isolated atoms*

TrendsTrends

Increase across a periodEffective nuclear charge increases

Decrease down a groupIncrease in atomic size and increase in electron shielding decreases the effective nuclear charge

Electronegativity depends upon: The number of protons in the nucleus The distance from the nucleus Electron shielding

Increase across a periodEffective nuclear charge increases

Decrease down a groupIncrease in atomic size and increase in electron shielding decreases the effective nuclear charge

Electronegativity depends upon: The number of protons in the nucleus The distance from the nucleus Electron shielding

Electronegativity TrendsElectronegativity TrendsINCREASES

INC

RE

AS

ES