THE MODERN PERIODIC TABLE. Mendeleev 1834 - 1907 1869 – Dmitri Mendeleev published the first...

THE MODERN THE MODERN PERIODIC TABLEPERIODIC TABLE

MendeleevMendeleev

1834 - 19071834 - 1907 1869 – Dmitri 1869 – Dmitri

Mendeleev Mendeleev published the first published the first periodic tableperiodic table

MendeleevMendeleev

Born in Siberia, the last Born in Siberia, the last of 14-17 childrenof 14-17 children

Father blind, mother ran Father blind, mother ran glass factoryglass factory

When he finished high When he finished high school, his father died school, his father died and the factory burnt and the factory burnt downdown

MendeleevMendeleev

His mother took His mother took him to St. him to St. Petersburg to study Petersburg to study sciencescience

Denied admission Denied admission to the university, he to the university, he studied at a school studied at a school for teachersfor teachers

MendeleevMendeleev

In time, he became In time, he became a professor of a professor of chemistry at the U. chemistry at the U. of St. Petersburgof St. Petersburg

While writing a While writing a chemistry chemistry textbook, he textbook, he developed the developed the periodic tableperiodic table

MendeleevMendeleev Where a gap existed in Where a gap existed in

his table, he predicted his table, he predicted a new element would a new element would be found and deduced be found and deduced its propertiesits properties

He was right. Three He was right. Three elements were found elements were found during his lifetimeduring his lifetime

Ga, Sc, GeGa, Sc, Ge

MendeleevMendeleev

The discovered The discovered elements provided the elements provided the strongest support for strongest support for his periodic tablehis periodic table

It is a cornerstone in It is a cornerstone in chemistry and in our chemistry and in our understanding of how understanding of how the universe is put the universe is put togethertogether

MendeleevMendeleev

Mendeleev’s Mendeleev’s table arranged table arranged the elements in the elements in order of order of increasing increasing atomic massatomic mass

Modern Periodic TableModern Periodic Table


Square of the periodic table contains anSquare of the periodic table contains an

element’s atomic #, chemical symbol, element’s atomic #, chemical symbol, atomic massatomic mass


An element’s An element’s properties can be properties can be predicted from its predicted from its location in the location in the periodic tableperiodic table

The elements in each The elements in each group have the same group have the same number of valence number of valence electronselectrons

METALSMETALS

Most elements are Most elements are metalsmetals

88 elements to the 88 elements to the left of the left of the “staircase” are “staircase” are metals or metal like metals or metal like elementselements

Physical Properties Physical Properties of Metalsof Metals

Luster (shininess)Luster (shininess) Good conductors of heat and Good conductors of heat and

electricityelectricity High density (heavy for their size)High density (heavy for their size) High melting pointHigh melting point Some metals (Fe, Co and Ni) are Some metals (Fe, Co and Ni) are

magneticmagnetic

Physical Properties Physical Properties of Metalsof Metals

Ductile (most metals can be drawn out Ductile (most metals can be drawn out into thin wires)into thin wires)

Malleable (most metals can be Malleable (most metals can be hammered into thin sheets)hammered into thin sheets)

METALSMETALS

Chemical Properties Chemical Properties of Metalsof Metals

Metals show a wide Metals show a wide range of chemical range of chemical propertiesproperties

Reactivity – ease and Reactivity – ease and speed with which an speed with which an element combines, or element combines, or reacts with other reacts with other elements and elements and compoundscompounds


Some metals are Some metals are very reactive, some very reactive, some do not react easilydo not react easily

AlloyAlloy – mixture of – mixture of metalsmetals

Examples: bronze, Examples: bronze, brass, stainless brass, stainless steelsteel


Easily lose electronsEasily lose electrons Corrode easily. Corrosion is a gradual Corrode easily. Corrosion is a gradual

wearing awaywearing away Examples of corrosion: silver Examples of corrosion: silver

tarnishing and iron rustingtarnishing and iron rusting

Families of MetalsFamilies of Metals

Group 1 – Alkali MetalsGroup 1 – Alkali Metals


Li Li

Na Na

One valence One valence electronelectron

Most reactiveMost reactive SoftSoft Low densitiesLow densities Low melting pointLow melting point


Combine with Combine with negative ions to negative ions to form saltsform salts


Na, KNa, K Na compounds in Na compounds in

large amounts in large amounts in sea watersea water

Na and K both Na and K both essential for lifeessential for life

Group 2 – Alkaline Earth MetalsGroup 2 – Alkaline Earth Metals

Two valence Two valence electronselectrons

Very reactiveVery reactive

Group 2 – AlkalineGroup 2 – AlkalineEarth MetalsEarth Metals

Magnesium and Magnesium and calcium are common calcium are common alkaline earth metalsalkaline earth metals

Calcium compounds Calcium compounds make up much of your make up much of your bones and teethbones and teeth

Group 2 – AlkalineGroup 2 – AlkalineEarth MetalsEarth Metals

Magnesium, when Magnesium, when combined with combined with aluminum, makes a aluminum, makes a strong but strong but lightweight alloylightweight alloy

Group 2 – Alkaline Earth MetalsGroup 2 – Alkaline Earth Metals

Transition MetalsTransition Metals


Elements in Groups Elements in Groups 3 – 12 3 – 12

Bridge between very Bridge between very reactive metals on reactive metals on left side and less left side and less reactive metals on reactive metals on the right sidethe right side


Transition metals Transition metals are fairly stableare fairly stable

React slowly or not React slowly or not at allat all

Rare Earth MetalsRare Earth Metals

Lanthanides and Lanthanides and ActinidesActinides

Lanthanides are Lanthanides are soft, shiny metals soft, shiny metals with high with high conductivityconductivity

Actinides are all Actinides are all radioactive. Some radioactive. Some not found in naturenot found in nature

NONMETALSNONMETALS

Nonmetals are found to the right of the Nonmetals are found to the right of the stair step linestair step line

17 elements17 elements Make up most of the human bodyMake up most of the human body

Physical Properties of NonmetalsPhysical Properties of Nonmetals

The physical properties of The physical properties of nonmetals are opposite to nonmetals are opposite to those of metalsthose of metals

Physical PropertiesPhysical Propertiesof Nonmetalsof Nonmetals

No luster (dull appearance)No luster (dull appearance) Poor conductor of heat and electricityPoor conductor of heat and electricity Brittle (breaks easily)Brittle (breaks easily) Not ductileNot ductile Many are gases at room temperatureMany are gases at room temperature

Physical PropertiesPhysical Propertiesof Nonmetalsof Nonmetals

Not malleableNot malleable Low densityLow density Low melting pointLow melting point Elements in this group have one Elements in this group have one

valence electronvalence electron How does this affect their reactivity?How does this affect their reactivity? It makes them It makes them VERY REACTIVE.VERY REACTIVE.

Chemical Properties Chemical Properties on Nonmetalson Nonmetals

Have many electrons in their highest Have many electrons in their highest energy levelenergy level

Form negative ionsForm negative ions Gain electronsGain electrons Noble gases do not react with other Noble gases do not react with other

elementselements

Chemical PropertiesChemical Propertiesof Nonmetalsof Nonmetals

Diatomic molecule Diatomic molecule – when nonmetals form – when nonmetals form molecules of two identical atomsmolecules of two identical atoms

H HH H

METALLOIDSMETALLOIDS

Elements that Elements that border the zigzag border the zigzag line have properties line have properties of both metals and of both metals and nonmetalsnonmetals

These elements are These elements are called called metalloidsmetalloids..

Physical PropertiesPhysical Propertiesof Metalloidsof Metalloids

SolidsSolids Can be shiny or dullCan be shiny or dull DuctileDuctile MalleableMalleable Conduct heat and electricity better Conduct heat and electricity better

than nonmetals, but not as well as than nonmetals, but not as well as metalsmetals

Physical PropertiesPhysical Propertiesof Metalloidsof Metalloids

Some are Some are semiconductors, semiconductors, such as Si (silicon)such as Si (silicon)

Boron GroupBoron Group Boron is the only Boron is the only

element in group 13 element in group 13 that is not a metalthat is not a metal

B is brittle, black B is brittle, black metalloidmetalloid

Al is the most Al is the most abundant metal in the abundant metal in the earth’s crustearth’s crust

Aluminum has many Aluminum has many usesuses

Carbon GroupCarbon Group

Carbon is the only Carbon is the only nonmetal in Group nonmetal in Group 1414

Two common forms Two common forms – graphite and – graphite and diamonddiamond

Each element has Each element has four valence four valence electronselectrons

Group 14 – Carbon GroupGroup 14 – Carbon Group

Carbon is the Carbon is the element essential element essential for lifefor life

It is unique because It is unique because it can link up with it can link up with other C atoms to other C atoms to form long chainsform long chains

Carbon GroupCarbon Group

Si and Ge are Si and Ge are metalloidsmetalloids

Sn and Pb are Sn and Pb are metalsmetals

Group 15 – Nitrogen GroupGroup 15 – Nitrogen Group

N and P are nonmetalsN and P are nonmetals N makes up 80% of airN makes up 80% of air N is essential to lifeN is essential to life N-fixing bacteria take N-fixing bacteria take

N from air and change N from air and change into compounds into compounds plants can useplants can use

Group 15 – Nitrogen GroupGroup 15 – Nitrogen Group

P (Phosphorus) P (Phosphorus) also necessary for also necessary for lifelife

P in bones, teeth P in bones, teeth and DNAand DNA

As and Sb are As and Sb are metalloidsmetalloids

Group 16 – Oxygen GroupGroup 16 – Oxygen Group

O is the most O is the most abundant element abundant element on earthon earth

O is very reactive O is very reactive and can combine and can combine with almost every with almost every other elementother element

S, Se are also S, Se are also nonmetalsnonmetals

Group 17 -- HalogensGroup 17 -- Halogens

Halogen means Halogen means “salt-former”“salt-former”

Halogens combine Halogens combine with metals to form with metals to form saltssalts

Have 7 valence Have 7 valence electronselectrons

F is the most F is the most reactive nonmetalreactive nonmetal

Group 18 – The Noble GasesGroup 18 – The Noble Gases

Colorless gasesColorless gases Do not combine Do not combine

with other elementswith other elements Outer electron shell Outer electron shell

is fullis full

Group 18 – The Noble GasesGroup 18 – The Noble Gases

He is the second He is the second lightest gaslightest gas

HydrogenHydrogen

H does not fit in H does not fit in with any groupwith any group

Reacts easily with Reacts easily with other elementsother elements

Can act like a metal Can act like a metal or a nonmetalor a nonmetal

QUIZ YOURSELF!QUIZ YOURSELF!

What are the rows What are the rows across the periodic across the periodic table called?table called?

Answer:Answer:

PERIODSPERIODS


What is the term for What is the term for the vertical the vertical columns in the columns in the Periodic Table?Periodic Table?

Answer: Groups or Answer: Groups or FamiliesFamilies


How are the elements arranged in the How are the elements arranged in the periodic table?periodic table?

In order of increasing atomic numberIn order of increasing atomic number


What is the most What is the most reactive group of reactive group of metals?metals?

THE MODERN PERIODIC TABLE. Mendeleev 1834 - 1907 1869 – Dmitri Mendeleev published the first...

Documents

Transcript of THE MODERN PERIODIC TABLE. Mendeleev 1834 - 1907 1869 – Dmitri Mendeleev published the first...