1.Tutorial on Periodic Trend, Effective Nuclear Charge and Physical Properties for Period 2 and 3.Prepared by Lawrence Kok http://lawrencekok.blogspot.com

2. Periodic Table of elements divided to Groups, Periods and BlocksPeriod- Horizontal row 7 periods/row Same number of shellGroup 1 Periods 17Groups Vertical column Same number of valence electron Same number outmost electronsBlock different region in periodic table s, p, d, f blocks s block- elements with valence e in s sublevel p block elements with valence e in p sublevel18 3. Periodic Table of elements divided to Groups, Periods and BlocksPeriod- Horizontal row 7 periods/row Same number of shellGroups Vertical column Same number of valence electron Same number outmost electronsBlock different region in periodic table s, p, d, f blocks s block- elements with valence e in s sublevel p block elements with valence e in p sublevelGroup 118Periods 17Excellent site from periodic videos Click here to views block - s orbitals partially filld block d orbitals partially fillp block p orbital partially fillf block f orbital partially fill 4. s block elements s orbitals partially fill1H Hep block elements p orbital partially fill51s2 n = 2 period 2B[He] 2s2 2p161s12Periodic Table s, p d, f blocks elementsC[He] 2s2 2p27N[He] 2s2 2p33Li[He] 2s18O[He] 2s2 2p44Be[He] 2s29F[He] 2s2 2p510Ne[He] 2s2 2p613Al[Ne] 3s2 3p13s111Na[Ne]12Mg[Ne] 3s214 20K Ca[Ne] 3s2 3p2[Ar]15P[Ne] 3s2 3p3[Ar]4s216S[Ne] 3s2 3p41719Si4s1CI[Ne] 3s2 3p518Ar[Ne] 3s2 3p6d block elements d orbitals partially fill transition elements21Sc[Ar] 4s2 3d122Ti[Ar] 4s2 3d223V[Ar] 4s2 3d1324Cr[Ar] 4s1 3d525Mn[Ar] 4s2 3d526Fe[Ar] 4s2 3d627Co[Ar] 4s2 3d728Ni[Ar] 4s2 3d829Cu[Ar] 4s1 3d1030Zn[Ar] 4s2 3d10f block elements f orbitals partially fill 5. s block elements s orbitals partially fill1H Hep block elements p orbital partially fill51s2 n = 2 period 2B[He] 2s2 2p161s12Periodic Table s, p d, f blocks elementsC[He] 2s2 2p27N[He] 2s2 2p33Li[He] 2s18O[He] 2s2 2p44Be[He] 2s29F[He] 2s2 2p510Ne[He] 2s2 2p613Al[Ne] 3s2 3p13s111Na[Ne]12Mg[Ne] 3s214 20K Ca[Ne] 3s2 3p2[Ar]15P[Ne] 3s2 3p3[Ar]4s216S[Ne] 3s2 3p41719Si4s1CI[Ne] 3s2 3p518Ar[Ne] 3s2 3p6d block elements d orbitals partially fill transition elements21Sc[Ar] 4s2 3d122Ti[Ar] 4s2 3d223V[Ar] 4s2 3d1324Cr[Ar] 4s1 3d525Mn[Ar] 4s2 3d526Fe[Ar] 4s2 3d627Co[Ar] 4s2 3d728Ni[Ar] 4s2 3d829Cu[Ar] 4s1 3d1030Zn[Ar] 4s2 3d10f block elements f orbitals partially fillVideo on electron configurationClick here electron structureClick here video on s,p,d,f notationClick here video s,p,d,f blocks, 6. Periodicity Predicted pattern/trends in physical/chemical properties across period. Physical propertiesPhysical change - without change in molecular composition. appearance change - composition remain unchanged.Element properties Color, texture, odor Density, hardness, ductility Brittleness, Malleability Melting /boiling point Solubility, polarityAtomic properties Ionization energy Atomic radii Ionic radii ElectronegativityChemical propertiesChemical change diff composition from original substances - chemical bonds broken/ formed - new products formed 7. Periodicity Predicted pattern/trends in physical/chemical properties across period. Physical propertiesChemical propertiesPhysical change - without change in molecular composition. appearance change - composition remain unchanged.Element properties Atomic properties Color, texture, odor Density, hardness, ductility Brittleness, Malleability Melting /boiling point Solubility, polarity Ionization energyPeriodic Trends Across period 2/3 Down group 1/17Atomic/ionic radiiGp 1Ionization energy Atomic radii Ionic radii ElectronegativityMelting pointElectronegativityGp 17 period 2 period 3Chemical change diff composition from original substances - chemical bonds broken/ formed - new products formed 8. Ionization energy (IE) 1st Ionization energy Min energy to remove 1 mole e from 1 mole of element in gaseous state M(g) M+ (g) + e2nd Ionization energy Min energy to remove 1 mole e from 1 mole of +1 ion to form +2 ion M+(g) M2+ (g) + eIonization energyWhy IE increases across the period? Why IE decreases down a group ? 9. Ionization energy (IE) 1st Ionization energy Min energy to remove 1 mole e from 1 mole of element in gaseous state M(g) M+ (g) + e2nd Ionization energy Min energy to remove 1 mole e from 1 mole of +1 ion to form +2 ion M+(g) M2+ (g) + eIonization energyFactors affecting ionization energy1Distance from nucleus electronDistance near to nucleus IE High Distance far away nucleus IE Low Distance near Strong electrostatic forces attraction bet nucleus and e IE High Why IE increases across the period? Why IE decreases down a group ? 10. Why IE increases across the period? Why IE decreases down a group ?Ionization energy (IE) 1st Ionization energy Min energy to remove 1 mole e from 1 mole of element in gaseous state M(g) M+ (g) + e2nd Ionization energy Min energy to remove 1 mole e from 1 mole of +1 ion to form +2 ion M+(g) M2+ (g) + eIonization energyFactors affecting ionization energy12Distance from nucleusNuclear chargeelectron+3+4+5+6Nuclear charge increaseDistance near to nucleus IE High Distance far away nucleus IE Low Nuclear charge high (more proton) IE High Nuclear charge low (less proton) IE Low +6Distance nearNuclear charge Strong electrostatic forces attraction bet nucleus and eStrong electrostatic forces attraction bet nucleus and eIE High IE High 11. Why IE increases across the period? Why IE decreases down a group ?Ionization energy (IE) 1st Ionization energy Min energy to remove 1 mole e from 1 mole of element in gaseous state M(g) M+ (g) + e2nd Ionization energy Min energy to remove 1 mole e from 1 mole of +1 ion to form +2 ion M+(g) M2+ (g) + eIonization energyFactors affecting ionization energy12Distance from nucleus3Nuclear chargeelectron+3+4+5+6Effective Nuclear Charge (ENC)/(Zeff) Screening effect/shielding Effective nuclear charge (ENC)/(Zeff) (Zeff) = Nuclear charge (Z) shielding effect Net positive charge felt by valence electrons.Nuclear charge increaseDistance near to nucleus IE High Distance far away nucleus IE Low Nuclear charge high (more proton) IE High Nuclear charge low (less proton) IE Low +6Inner electron shield valence e from positive nuclear charge Distance nearNuclear charge Higher electron/electron repulsionStrong electrostatic forces attraction bet nucleus and eStrong electrostatic forces attraction bet nucleus and eEasier valence e to leaveIE High IE High IE Low 12. IE drop from Be to B and N to OIonization Energy- Period 2Why IE increases across the period 2? IE increases across period 2 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6 13. IE drop from Be to B and N to OIonization Energy- Period 2Why IE increases across the period 2? IE increases across period 2 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p1IE drop from Be to BElectron in p sublevel of B further away from nucleusWeak electrostatic force attraction between nucleus and electronIE - Low 1s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6 14. IE drop from Be to B and N to OIonization Energy- Period 2Why IE increases across the period 2? IE increases across period 2 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p2IE drop from Be to B1s2 2s2 2p31s2 2s2 2p4IE drop from N to OElectron in p sublevel of B further away from nucleus2 electrons in same p orbital - Greater e/e repulsionWeak electrostatic force attraction between nucleus and electronEasier to remove e IE - Low IE - Low period 21s2 2s2 2p51s2 2s2 2p6 15. IE drop from Mg to AI and P to SIonization Energy- Period 3Why IE increases across the period 3? IE increases across period 3 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High NaMgAISiPSCIAr3p3s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p1[Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4[Ne] 3s2 3p5[Ne] 3s2 3p6 16. IE drop from Mg to AI and P to SIonization Energy- Period 3Why IE increases across the period 3? IE increases across period 3 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High NaMgAISiPSCIAr3p3s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p1IE drop from Mg to AIElectron in p sublevel of AI further away from nucleus Weak electrostatic force attraction between nucleus and electronIE - Low [Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4[Ne] 3s2 3p5[Ne] 3s2 3p6 17. IE drop from Mg to AI and P to SIonization Energy- Period 3Why IE increases across the period 3? IE increases across period 3 Nuclear charge increase Strong electrostatic forces attraction bet nucleus and eIE High NaMgAISiPSCIAr3p3s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p1[Ne] 3s2 3p2IE drop from Mg to AI[Ne] 3s2 3p3[Ne] 3s2 3p4IE drop from P to SElectron in p sublevel of AI further away from nucleus2 electrons in same p orbital - Greater e/e repulsionWeak electrostatic force attraction between nucleus and electronEasier to remove e IE - Low IE - Low Period 3[Ne] 3s2 3p5[Ne] 3s2 3p6 18. IE for Period 2 and 3Ionization Energy- Period 2 and 3Why IE period 3 lower than 2? Period 3 3 shells/energy levelperiod 2 Period 3Valence e further from nucleusHigh shielding effect more inner eWeaker electrostatic forces attraction bet nucleus and e IE Lower period 2 LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6Period 3 NaMgAISiPS[Ne] 3s2 3p1[Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4CIAr3rd level3p 3s 2p 2s 1s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p5[Ne] 3s2 3p6 19. IE for Period 2 and 3Ionization Energy- Period 2 and 3Why IE period 3 lower than 2? Period 3 3 shells/energy levelperiod 2 Period 3Valence e further from nucleusHigh shielding effect more inner eWeaker electrostatic forces attraction bet nucleus and e IE Lower period 2 LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6Period 3 NaMgAISiPS[Ne] 3s2 3p1[Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4CIAr3rd level3p 3s 2p 2s 1s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p5[Ne] 3s2 3p6 20. IE for Ne and ArIonization Energy- Period 2 and 3Why Ne and Ar have HIGH IE ? Full electron configuration, 2.8/2.8.8neon argonMost energetically stable structure Difficult to lose electronIE High period 2 LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6Period 3 NaMgAISiPS[Ne] 3s2 3p1[Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4CIAr3p3s 2p 2s 1s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p5[Ne] 3s2 3p6 21. IE for Ne and ArIonization Energy- Period 2 and 3Why Ne and Ar have HIGH IE ? Full electron configuration, 2.8/2.8.8neon argonMost energetically stable structure Difficult to lose electronIE High period 2 LiBeBCNOFNe2p 2s 1s 1s2 2s11s2 2s21s2 2s2 2p11s2 2s2 2p21s2 2s2 2p31s2 2s2 2p41s2 2s2 2p51s2 2s2 2p6Period 3 NaMgAISiPS[Ne] 3s2 3p1[Ne] 3s2 3p2[Ne] 3s2 3p3[Ne] 3s2 3p4CIAr3p3s 2p 2s 1s [Ne] 3s1[Ne] 3s2[Ne] 3s2 3p5[Ne] 3s2 3p6 22. Atomic Radius Distance between nucleus and outmost electrons. Atom not like a ball cant measure its radius directly Uncertain about position of electron uncertain of atomic radius Uncertain abt electrons positionHow to measure atomic radius?Half the distance bet nuclei of two closest identical atoms.Atomic radius 23. Atomic Radius Distance between nucleus and outmost electrons.Atomic radiusAtom not like a ball cant measure its radius directly Uncertain about position of electron uncertain of atomic radius Uncertain abt electrons positionHow to measure atomic radius?Half the distance bet nuclei of two closest identical atoms. Atomic RadiusCovalent MoleculeNoble gas Monoatomic atomsDepend on type of bonding covalent or metallicMetallic elementsIonic compounds bond length bond length bond lengthCovalent RadiusVan Der Waals radius bond length of 2 atom bond length of nuclei atoms not bonded together (noble gas)Metallic radius bond length bet nuclei of neighbouring metal ionsIonic radius Measure indirectly using internucleus distance 24. Atomic Radius Distance between nucleus and outmost electrons.Atomic radius Atom not like a ball cant measure its radius directly Uncertain about position of electron uncertain of atomic radius Uncertain abt electrons positionHow to measure atomic radius?Half the distance bet nuclei of two closest identical atoms. Atomic RadiusCovalent MoleculeNoble gas Monoatomic atomsDepend on type of bonding covalent or metallicMetallic elementsIonic compounds bond length bond length bond lengthCovalent RadiusVan Der Waals radius bond length of 2 atom bond length of nuclei atoms not bonded together (noble gas)Click here video on atomic radiusMetallic radius bond length bet nuclei of neighbouring metal ionsClick here video on atomic radiusIonic radius Measure indirectly using internucleus distanceClick here video on atomic radius 25. Effective Nuclear Charge (ENC)/(Zeff) Screening effect/shielding Effective nuclear charge (ENC)/(Zeff) (Zeff) = Nuclear charge (Z) shielding effect Net positive charge felt by valence electrons.Effective nuclear chargeEffective nuclear charge magnesium (2.8.2) net +2 10 inner electron shield 12+ protons Valence electron feel a net (12-10 = +2) Effective nuclear charge, (Zeff) = +2 26. Effective Nuclear Charge (ENC)/(Zeff) Screening effect/shielding Effective nuclear charge (ENC)/(Zeff) (Zeff) = Nuclear charge (Z) shielding effect Net positive charge felt by valence electrons.Effective nuclear chargeEffective nuclear charge magnesium (2.8.2) net +2 10 inner electron shield 12+ protons Valence electron feel a net (12-10 = +2) Calculate Z(eff) and atomic radius for Li Effective nuclear charge, (Zeff) = +21Calculate Z(eff) for LiFormula ionization energy2nd energy level n=2 Z2 IE =1312 2 n Z2 521 =1312 2 2 Zeff = +1.26 1st IE Li = 521kJ/mol2 inner electron shield 3+ protonsValence electron felt a net (3-2) = +1Z(eff) = +1.26 NOT +1 (calculation shown above)Lithium (2.1) 27. Effective Nuclear Charge (ENC)/(Zeff) Screening effect/shielding Effective nuclear charge (ENC)/(Zeff) (Zeff) = Nuclear charge (Z) shielding effect Net positive charge felt by valence electrons.Effective nuclear chargeEffective nuclear charge magnesium (2.8.2) net +2 10 inner electron shield 12+ protons Valence electron feel a net (12-10 = +2) Calculate Z(eff) and atomic radius for Li Effective nuclear charge, (Zeff) = +212Calculate Z(eff) for LiFormula ionization energy2nd energy level n=2Lithium (2.1) Z2 IE =1312 2 n Z2 521 =1312 2 2 Zeff = +1.26 1st IE Li = 521kJ/mol2 inner electron shield 3+ protonsValence electron felt a net (3-2) = +1Z(eff) = +1.26 NOT +1 (calculation shown above)RCalculate atomic radius Li using Z(eff)Fcentripetal = Fcoulomb mv 2 kqZ = 2 r R 2 mh kqZ = m 2p 2 R 2 Rh2 R= mp 2 kqZR =168pmh h l= = p mvh v= ml v=h2nd energy level n=2n=2 2 l = 2p Rl =pRmp Rm = mass electron -9.1 x 10-31 h = plank constant 6.626 x 10-34 k = coulomb constant 9.0 x 109 q = charge electron 1.6 x 10-19 Z = effective nuclear charge - +1.26 28. Effective Nuclear Charge (ENC)/(Zeff) Screening effect/shielding Effective nuclear charge (ENC)/(Zeff) (Zeff) = Nuclear charge (Z) shielding effect Net positive charge felt by valence electrons.Effective nuclear chargeEffective nuclear charge magnesium (2.8.2) net +2 10 inner electron shield 12+ protons Valence electron feel a net (12-10 = +2) Calculate Z(eff) and atomic radius for Li Effective nuclear charge, (Zeff) = +212Calculate Z(eff) for LiFormula ionization energy2nd energy level n=2Lithium (2.1) Z2 IE =1312 2 n Z2 521 =1312 2 2 Zeff = +1.26 1st IE Li = 521kJ/mol2 inner electron shield 3+ protonsRCalculate atomic radius Li using Z(eff)Fcentripetal = Fcoulomb mv 2 kqZ = 2 r R 2 mh kqZ = m 2p 2 R 2 Rh2 R= mp 2 kqZR =168pmh h l= = p mvh v= ml v=h2nd energy level n=2n=2 2 l = 2p Rl =pRmp Rm = mass electron -9.1 x 10-31 h = plank constant 6.626 x 10-34 k = coulomb constant 9.0 x 109 q = charge electron 1.6 x 10-19 Z = effective nuclear charge - +1.26Valence electron felt a net (3-2) = +1Z(eff) = +1.26 NOT +1 (calculation shown above) Click here video ENC LiClick here video calculating radius Li 29. Atomic Radius (Covalent radius)Atomic Radius- Period 2/3Why atomic radius decrease across period 2/3 Atomic radius decrease across period 2/3 Effective Nuclear charge increase Strong electrostatic forces attraction bet nucleus and e Size decrease 30. Atomic Radius (Covalent radius)Atomic Radius- Period 2/3Why atomic radius decrease across period 2/3 Atomic radius decrease across period 2/3 Effective Nuclear charge increase Strong electrostatic forces attraction bet nucleus and e Size decrease Li +3Be +4C +6N +7O +8F +9Effective Nuclear charge increase period 2Na +11period 3B +5Mg +12AI +13Si +14Effective Nuclear charge increase P +15S +16CI +17 31. Atomic Radius (Covalent radius)Atomic Radius- Period 2/3Why atomic radius decrease across period 2/3 Atomic radius decrease across period 2/3 Effective Nuclear charge increase Strong electrostatic forces attraction bet nucleus and e Size decrease Gp 17Li +3Be +4C +6N +7F +9O +8Effective Nuclear charge increase period 2Na +11period 3B +5Mg +12AI +13Si +14P +15S +16CI +17Effective Nuclear charge increase Why atomic radius increase down Gp 17? Screening/shielding effect increase Inner shell electrons electron electron repulsion increase Number shell increase Valence e further away from nucleusAtomic radius High 32. Positive Ions (+)Atomic and Ionic Radius- Period 2/3Ionic radii Positive ion (+) smallerDecrease in number of shells loss of electron Less electron electron repulsion Size decrease Comparison bet atomic/ionic radiiIonic radiiAtomic radii 33. Positive Ions (+)Atomic and Ionic Radius- Period 2/3Ionic radii Positive ion (+) smallerNegative Ions (-)Ionic radii Negative ion (-) biggerDecrease in number of shells loss of electronIncrease in number of shells gain of electronLess electron electron repulsionIncrease electron electron repulsionSize decrease Size increase Comparison bet atomic/ionic radiiComparison bet atomic/ionic radiiIonic radii Ionic radii Atomic radii Atomic radii 34. Positive Ions (+)Atomic and Ionic Radius- Period 2/3Ionic radii Positive ion (+) smallerNegative Ions (-)Ionic radii Negative ion (-) biggerDecrease in number of shells loss of electronIncrease in number of shells gain of electronLess electron electron repulsionIncrease electron electron repulsionSize decrease Size increase Comparison bet atomic/ionic radiiComparison bet atomic/ionic radiiIonic radii Ionic radii Atomic radii Atomic radiiNa2.8.1Na+2.8Mg2.8.2Mg2+2.8AI2.8.3AI3+2.8Atomic radii- 3 shellsIonic radii - 2 shellsSCI2.8.62.8.7S2-CI-2.8.82.8.8Atomic radii - 3 shellsIonic radii- 2 shells 35. Electronegativity Electronegativity (EN) Tendency of atom to attract/pull shared/bonding electron to itself EN value higher pull/attract electron higher (EN value from 0.7 4) Shared electron cloud closer to O EN lowestEN highestElectronegativity EN increase up a Group EN increase across a Period 36. Electronegativity Electronegativity (EN) Tendency of atom to attract/pull shared/bonding electron to itself EN value higher pull/attract electron higher (EN value from 0.7 4) Shared electron cloud closer to O EN highestEN lowest Factors affecting EN value Size of atom/distance small size/distance stronger attraction for electron Nuclear charge higher nuclear charge stronger attraction for electron Nuclear chargeEN increase across period 2Li +3Be +4B +5C +6N +7O +8F +9Period 2 EN increase across period 2Nuclear charge increase Strong attraction for electron EN increase Electronegativity EN increase up a Group EN increase across a Period 37. Electronegativity Electronegativity (EN) Tendency of atom to attract/pull shared/bonding electron to itself EN value higher pull/attract electron higher (EN value from 0.7 4) Shared electron cloud closer to O EN highestEN lowest Electronegativity EN increase up a Group EN increase across a PeriodFactors affecting EN value Size of atom/distance small size/distance stronger attraction for electron Nuclear charge higher nuclear charge stronger attraction for electronSizeGp 17 EN decrease down gp 17FSize increase Nuclear chargeCI Attraction electron decrease EN increase across period 2 EN lower Li +3Br Be +4B +5C +6N +7O +8F +9Period 2 I EN increase across period 2Nuclear charge increase Strong attraction for electron EN increase 38. Melting point across Period 2/3 Melting point down Gp 1/17Melting Point Temp when solid turn to liquid (temp remain constant) Energy absorb to overcome forces attraction bet moleculePeriod 2/3Gp 1Melting PointGp 17Factors affecting melting pointType of bonding/forcesStructure Metallic/Non Metallic structureCovalent structureSimple molecular structureIonic structureGiant molecular structureMetallic BondingCovalent BondingIonic Bonding 39. Melting point across Period 2/3 Melting point down Gp 1/17Melting Point Temp when solid turn to liquid (temp remain constant) Energy absorb to overcome forces attraction bet moleculePeriod 2/3Melting PointGp 1Gp 17Factors affecting melting pointType of bonding/forcesStructure Metallic/Non Metallic structureCovalent structureSimple molecular structureIonic structureMetallic BondingMelting point across Period 2 and 3Giant molecular structureperiod 2 C period 3BSiBe MgLiNa N O F NeAI P SCovalent BondingCIIonic Bonding 40. Melting point for metallic/non metallicCMelting PointMelting point across Period 2period 2B Be Li N O F Ne 41. Melting point for metallic/non metallicMelting point across Period 2Melting PointCperiod 2B Be Li N O F NeLiBeBCNOFNem/p (/C)180128023003730-210-218-220-249structuremetallicmetallicGiant covalentGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicGiant covalentGiant covalentSimple covalentSimple covalentSimple covalentSimple covalent Across period 2 m/p increase from Li C m/p drop from N Ne Metallic non metallic 42. Melting point for metallic/non metallicMelting point across Period 2Melting PointCperiod 2B Be Li N O F NeLiBeBCNOFNem/p (/C)180128023003730-210-218-220-249structuremetallicmetallicGiant covalentGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicGiant covalentGiant covalentSimple covalentSimple covalentSimple covalentSimple covalentMetallic bondingStrong attraction bet nucleus with sea of electrons High m/p Across period 2 m/p increase from Li C m/p drop from N Ne Metallic non metallic 43. Melting point for metallic/non metallicMelting point across Period 2Melting PointCperiod 2B Be Li N O F NeLiBeBCNOFNem/p (/C)180128023003730-210-218-220-249structuremetallicmetallicGiant covalentGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicGiant covalentGiant covalentSimple covalentSimple covalentSimple covalentSimple covalentMetallic bondingGiant covalentStrong attraction bet nucleus with sea of electronsMacromolecular structure with strong covalent bondsHigh m/pHighest m/p Across period 2 m/p increase from Li C m/p drop from N Ne Metallic non metallic 44. Melting point for metallic/non metallicMelting point across Period 2Melting PointCperiod 2B Be Li N O F NeLiBeBCNOFNem/p (/C)180128023003730-210-218-220-249structuremetallicmetallicGiant covalentGiant covalentSimple molecularSimple molecularSimple molecularmetallicmetallicGiant covalentGiant covalentSimple covalentSimple covalentSimple covalentAcross period 2 m/p increase from Li C m/p drop from N Ne Metallic non metallicMono atomicbonding Simple covalentMetallic bondingGiant covalentSimple covalentVan der waals forces bet moleculesStrong attraction bet nucleus with sea of electronsMacromolecular structure with strong covalent bondsHigh m/pHighest m/p Simple molecular weak Van Der Waals forces attraction bet molecules Low m/p 45. Melting point for metallic/non metallicMelting PointMelting point across Period 3Period 3Si Mg AINaP SCI Ar 46. Melting point for metallic/non metallicMelting point across Period 3Melting PointPeriod 3Si Mg AINaNaMgP SAICI ArSiPSCIArm/p (/C)98650660142344120-101-189structuremetallicmetallicmetallicGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicmetallicGiant covalentSimple covalentSimple covalentSimple covalentSimple covalent Across period 3 m/p increase from Na Si m/p drop from P Ar Metallic non metallic 47. Melting point for metallic/non metallicMelting point across Period 3Melting PointPeriod 3Si Mg AINaNaP SMgAICI ArSiPSCIArm/p (/C)98650660142344120-101-189structuremetallicmetallicmetallicGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicmetallicGiant covalentSimple covalentSimple covalentSimple covalentSimple covalentMetallic bondingStrong attraction bet nucleus with sea of electrons High m/p Across period 3 m/p increase from Na Si m/p drop from P Ar Metallic non metallic 48. Melting point for metallic/non metallicMelting point across Period 3Melting PointPeriod 3Si Mg AINaNaP SMgCI ArAISiPSCIArm/p (/C)98650660142344120-101-189structuremetallicmetallicmetallicGiant covalentSimple molecularSimple molecularSimple molecularMono atomicbondingmetallicmetallicmetallicGiant covalentSimple covalentSimple covalentSimple covalentSimple covalentMetallic bondingGiant covalentStrong attraction bet nucleus with sea of electronsMacromolecular structure with strong covalent bondsHigh m/pHighest m/p Across period 3 m/p increase from Na Si m/p drop from P Ar Metallic non metallic 49. Melting point for metallic/non metallicMelting point across Period 3Melting PointPeriod 3Si Mg AINaNaP SMgCI ArAISiPSCIArm/p (/C)98650660142344120-101-189structuremetallicmetallicmetallicGiant covalentSimple molecularSimple molecularSimple molecularmetallicmetallicmetallicGiant covalentSimple covalentSimple covalentSimple covalentAcross period 3 m/p increase from Na Si m/p drop from P Ar Metallic non metallicMono atomicbonding Simple covalentMetallic bondingGiant covalentSimple covalentVan der waals forces between moleculesStrong attraction bet nucleus with sea of electronsMacromolecular structure with strong covalent bondsHigh m/pHighest m/p Simple molecular weak Van Der Waals forces attraction bet molecules Low m/p 50. Atomic Radius- Group 1 and 17Ionization Energy Group 1 and 17Atomic RadiusAtomic RadiusAtomic RadiusGp 1shellMelting point Group 1 and 17Atomic RadiusIonization EnergyGp 17shellMelting pointGp 1Gp 17Gp 1Gp 17LiFLi2.1F2.7LiFNa2.8.1CI2.8.7NaCINaCIK2.8.8.12.8.18.7KBrKBrRbIRb2.8.8.18.1Br2.8.18.18.7IWhy atomic radius increase ? Number shell increase Valence e further away from nucleus Atomic radius High RbIIE decrease down group Number shell/energy level increase Valence e further away from nucleus Weak forces attraction bet nucleus and e IE Low m/p down Gp 1 Size increase Attraction bet nucleus and sea electrons decrease Metallic bonding Melting point m/p increase Gp 17 Size increase VDF increase IMF attraction bet molecules increase Melting point 51. Acknowledgements Thanks to source of pictures and video used in this presentation http://crescentok.com/staff/jaskew/isr/tigerchem/econfig/electron4.htm http://pureinfotech.com/wp-content/uploads/2012/09/periodicTable_20120926101018.png http://chemglobe.org/ptoe/Thanks to Creative Commons for excellent contribution on licenses http://creativecommons.org/licenses/Prepared by Lawrence Kok Check out more video tutorials from my site and hope you enjoy this tutorial http://lawrencekok.blogspot.com