PERIODIC PERIODIC TABLETABLE

MODERN PERIODIC TABLEMODERN PERIODIC TABLEDevelopment of the Modern Periodic TableDevelopment of the Modern Periodic Table

John Newland- arrange the elementarrange the elementaccording to the increasing order or relativeaccording to the increasing order or relativeatomic mass. Introduce atomic mass. Introduce Octave LawOctave Law

Dmitri Mendeleev-Dmitri Mendeleev- Successfully coined the first periodic table in year Successfully coined the first periodic table in year1869. arrange the element according to the increasing order of1869. arrange the element according to the increasing order ofRelative atomic mass. Left empty spaces for elements that not foundRelative atomic mass. Left empty spaces for elements that not foundyet at that time.yet at that time.

H.J.G. Moseley-H.J.G. Moseley- carried out X-Ray analysis and confirmed that the carried out X-Ray analysis and confirmed that theProton number is the identity of each element. He confirmed that theProton number is the identity of each element. He confirmed that theproton number and not the relative atomic mass that causes theproton number and not the relative atomic mass that causes theperiodicity of the properties Of the elements. Established the periodicity of the properties Of the elements. Established the ModernModernPeriodic TablePeriodic Table

The arrangement of elements in vertical column The arrangement of elements in vertical column called called GroupsGroups and horizontal rows called and horizontal rows called PeriodsPeriods in in order of increasing proton numberorder of increasing proton number

There are 18 Groups numbered 1-18 and 7 Periods There are 18 Groups numbered 1-18 and 7 Periods numbered 1-7 in a Periodic Table.numbered 1-7 in a Periodic Table.

MODERN PERIODIC TABLEMODERN PERIODIC TABLE

Periods & GroupsPeriods & Groups7 numbered periods: 7 numbered periods:

Period 1 : 2 elements, H and He.Period 1 : 2 elements, H and He.Period 2 : 8 elements, Li to Ne.Period 2 : 8 elements, Li to Ne.Period 3 : 8 elements, Na to Ar.Period 3 : 8 elements, Na to Ar.Period 4 : 18 elements, K to Kr, Period 4 : 18 elements, K to Kr,

(including First transition elements)(including First transition elements)Period 5 : 18 elements, Rb to Xe, Period 5 : 18 elements, Rb to Xe,

(including Second transition elements)(including Second transition elements)Period 6 : 32 elements, Cs to Rn,Period 6 : 32 elements, Cs to Rn,

(including Third transition elements & (including Third transition elements & Lanthanides)Lanthanides) Period 7 : variable no of elements, Fr to Mt,Period 7 : variable no of elements, Fr to Mt,

(including Fourth transition elements &(including Fourth transition elements & Actinides)Actinides)

PeriodsPeriods

Across the period from left to Across the period from left to rightright

Proton number increasesProton number increases Element become non-metallicElement become non-metallic Oxides become more acidicOxides become more acidic

GroupsGroups

Shared similar chemical properties (have sameShared similar chemical properties (have same

number of valence electrons).number of valence electrons). Have the same number of outer shell electronHave the same number of outer shell electron Form ion with the same chargeForm ion with the same charge Form the same number of bondsForm the same number of bonds Form compound with similar formulaForm compound with similar formula

Special names for some groups of elements :Special names for some groups of elements :

Group I (IA) : alkali metalsGroup I (IA) : alkali metals

Group 2 (IIA) : alkaline earth metalGroup 2 (IIA) : alkaline earth metal

Group 17 (VIIA) : halogensGroup 17 (VIIA) : halogens

Group 18 (VIIIA) : noble gasesGroup 18 (VIIIA) : noble gases

Classification of the ElementsClassification of the Elements

Common classificationCommon classification

classification into different block (s,p,d,f)classification into different block (s,p,d,f)

Valence electrons : Outer electrons of an atom, which are Valence electrons : Outer electrons of an atom, which are those involved in chemical bondingthose involved in chemical bonding

Electron configuration : tell us how the electron are Electron configuration : tell us how the electron are distributed among the various atomic orbital's) distributed among the various atomic orbital's)

based on selected physical properties of the elementbased on selected physical properties of the element

Alkali MetalsAlkali Metals

Found in group 1 of the periodic table (formerly known as group IA), Found in group 1 of the periodic table (formerly known as group IA), very reactive metals that do not occur freely in nature. very reactive metals that do not occur freely in nature.

Have only one electron in their outer shell. Therefore, they are readyHave only one electron in their outer shell. Therefore, they are readyTo lose that one electron in ionic bonding with other elements.To lose that one electron in ionic bonding with other elements.

The alkali metals are softer than most other metals. Cesium andThe alkali metals are softer than most other metals. Cesium andFrancium are the most reactive elements in this group. Alkali metalsFrancium are the most reactive elements in this group. Alkali metalscan explode if they are exposed to water. The Alkali Metals are: can explode if they are exposed to water. The Alkali Metals are:

LithiumLithium SodiumSodium PotassiumPotassium RubidiumRubidium CesiumCesium FranciumFrancium

CLASSIFICATION BASED ON ELECTRON CONFIGURATION

Alkaline earth metalAlkaline earth metal

Metallic elements found in the second group of the Metallic elements found in the second group of the periodic table. periodic table.

All alkaline earth elements have an oxidation number of All alkaline earth elements have an oxidation number of +2, making them very reactive. Because of their reactivity, +2, making them very reactive. Because of their reactivity, the alkaline metals are not found free in nature. the alkaline metals are not found free in nature.

The Alkaline Earth Metals are: The Alkaline Earth Metals are:

BerylliumBeryllium MagnesiumMagnesium CalciumCalcium StrontiumStrontium BariumBarium Radium Radium

Halogens Halogens Five non-metallic elements found in group 17 of the periodic table. Five non-metallic elements found in group 17 of the periodic table.

Have 7 electrons in their outer shells, giving them an oxidation Have 7 electrons in their outer shells, giving them an oxidation number of -1. number of -1.

The halogens exist, at room temperature, in all three states of The halogens exist, at room temperature, in all three states of matter:matter:

Solid- Iodine, Astatine Solid- Iodine, Astatine Liquid- Bromine Liquid- Bromine Gas- Fluorine, Chlorine Gas- Fluorine, Chlorine

The Halogens are: The Halogens are:

Fluorine Fluorine Chlorine Chlorine Bromine Bromine Iodine Iodine Astatine Astatine

NOBLE GASNOBLE GAS

The six noble gases are found in group 18 of the The six noble gases are found in group 18 of the periodic table. periodic table.

Have completely filled outer shell (8 electrons)Have completely filled outer shell (8 electrons)

Except for Helium, the valence electron is 2Except for Helium, the valence electron is 2

The noble gaseous are: The noble gaseous are:

HeliumHelium NeonNeon ArgonArgon CryptonCrypton XenonXenon RadonRadon

CLASSIFICATION INTO METALS, METALLOIDS CLASSIFICATION INTO METALS, METALLOIDS AND NON-METALS AND NON-METALS

Elements from top of Group 13 (B) to the bottom of Group 16Elements from top of Group 13 (B) to the bottom of Group 16

(Po) separates the elements into 3 classes(Po) separates the elements into 3 classes

METALMETAL

Most metals elements exhibit the shiny lusterMost metals elements exhibit the shiny luster

Metals tend to lose valence electron during chemicalMetals tend to lose valence electron during chemical

change, forming positive ions called cations. change, forming positive ions called cations.

NON-METALSNON-METALS

• Elements in groups 14-16 of the periodic table. Elements in groups 14-16 of the periodic table. • Not able to conduct electricity or heat very well. Not able to conduct electricity or heat very well. • Exist in two of the three states of matter. At room temperature: Exist in two of the three states of matter. At room temperature:

gases (such as oxygen) and solids (such as carbon).gases (such as oxygen) and solids (such as carbon).

• They have oxidation numbers of ±4, -3, and -2. They have oxidation numbers of ±4, -3, and -2.

• The Non-Metal elements are: The Non-Metal elements are:

• HydrogenHydrogen • CarbonCarbon • NitrogenNitrogen • OxygenOxygen • PhosphorusPhosphorus • SulfurSulfur • SeleniumSelenium

MetalloidsMetalloids

Elements found along the stair-step line that distinguishes metals Elements found along the stair-step line that distinguishes metals from non-metals. from non-metals.

This line is drawn from between Boron and Aluminum to the border This line is drawn from between Boron and Aluminum to the border between Polonium and Astatine. between Polonium and Astatine.

Metalloids have properties of both metals and non-metals. Some of the Metalloids have properties of both metals and non-metals. Some of the metalloids, such as silicon and germanium, are semi-conductors. This metalloids, such as silicon and germanium, are semi-conductors. This means that they can carry an electrical charge under special means that they can carry an electrical charge under special conditions. This property makes metalloids useful in computers and conditions. This property makes metalloids useful in computers and calculators calculators

The Metalloids are: The Metalloids are:

BoronBoron SiliconSilicon GermaniumGermanium ArsenicArsenic AntimonyAntimony TelluriumTellurium PoloniumPolonium

Physical properties of metals and non-Physical properties of metals and non-metalsmetals

MetalsMetals

High electrical conductivity High electrical conductivity

High thermal conductivityHigh thermal conductivity

Metallic gray or silver lusterMetallic gray or silver luster

Almost all are solidsAlmost all are solids

Can be hammered into sheetCan be hammered into sheet

Non MetalsNon Metals

Poor electrical conductivityPoor electrical conductivity

Good heat insulators No Good heat insulators No metallic lustermetallic luster

Solids, liquids or gasesSolids, liquids or gases

Brittle in solid stateBrittle in solid state

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