IIIIII Periodic Trends Ch. 5 - The Periodic Table

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

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

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

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

zAtomic Radius D. Atomic Radius Li Ar Ne K Na

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

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

Electronegativity zThe tendency of an atom to attract electrons to form ionic bonds.

zElectronegativity Trend zIncreases up and to the right.

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

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

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

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

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

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

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

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

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

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

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