IIIIII C. Johannesson III. Periodic Trends (p ) Ch. 5 - The Periodic Table

C. Johannesson A. Periodic Law zWhen elements are arranged in order of increasing atomic #, elements with similar properties appear at regular intervals.

C. Johannesson B. Chemical Reactivity zFamilies ySimilar valence e - within a group result in similar chemical properties

C. Johannesson B. Chemical Reactivity zAlkali Metals zAlkaline Earth Metals zTransition Metals zHalogens zNoble Gases

C. Johannesson zAtomic Radius ysize of atom © 1998 LOGAL zFirst Ionization Energy yEnergy required to remove one e - from a neutral atom. © 1998 LOGAL zMelting/Boiling Point C. Other Properties

C. Johannesson zAtomic Radius D. Atomic Radius Li Ar Ne K Na

C. Johannesson zAtomic Radius yIncreases to the LEFT and DOWN D. Atomic Radius

C. Johannesson zWhy larger going down? yHigher energy levels have larger orbitals yShielding - core e - block the attraction between the nucleus and the valence e - zWhy smaller to the right? yIncreased nuclear charge without additional shielding pulls e - in tighter D. Atomic Radius

C. Johannesson zFirst Ionization Energy E. Ionization Energy K Na Li Ar Ne He

C. Johannesson zFirst Ionization Energy yIncreases UP and to the RIGHT E. Ionization Energy

C. Johannesson zWhy opposite of atomic radius? yIn small atoms, e - are close to the nucleus where the attraction is stronger zWhy small jumps within each group? yStable e - configurations don’t want to lose e - E. Ionization Energy

C. Johannesson zSuccessive Ionization Energies yMg1st I.E.736 kJ 2nd I.E.1,445 kJ Core e - 3rd I.E.7,730 kJ yLarge jump in I.E. occurs when a CORE e - is removed. E. Ionization Energy

C. Johannesson yAl1st I.E.577 kJ 2nd I.E.1,815 kJ 3rd I.E.2,740 kJ Core e - 4th I.E.11,600 kJ zSuccessive Ionization Energies yLarge jump in I.E. occurs when a CORE e - is removed. E. Ionization Energy

C. Johannesson zMelting/Boiling Point yHighest in the middle of a period. F. Melting/Boiling Point

C. Johannesson zIonic Radius yCations (+) xlose e - xsmaller © 2002 Prentice-Hall, Inc. yAnions (–) xgain e - xlarger G. Ionic Radius

C. Johannesson zWhich atom has the larger radius? yBe orBa yCa orBr Ba Ca Examples

C. Johannesson zWhich atom has the higher 1st I.E.? yNorBi yBa orNe N Ne Examples

C. Johannesson zWhich atom has the higher melting/boiling point? yLiorC yCrorKr C Cr Examples

C. Johannesson zWhich particle has the larger radius? ySorS 2- yAlorAl 3+ S 2- Al Examples

C. Johannesson Electronegativity z Atoms ability to attract electrons z Increases across a period, but there are exceptions; z ↑ electronegativity elements in upper right p block z ↓ electronegativity elements in lower left s block. z SEE page 151

C. Johannesson Electron Affinity z the energy change that occurs when a neutral atom gains an electron z see p. 147 figure 5-17 z generally decreases from left to right on the table.

C. Johannesson