PERIODIC PROPERTIES

FOUR PERIODIC PROPERTIES: 1. Atomic Radius/Ionic Radius

2. Metallic Character 3. Ionization Energy 4. Electronegativity

ATOMIC RADIUS What is it? The distance from the

nucleus to the outer/valence energy level.

Small atomic radius Large atomic

radius

THE TREND FOR ATOMIC RADIUSIncreases

Incr

ease

s

WHY THE TREND WITHIN THE PERIOD? As you go from left to right the atomic

radius gets smaller. BUT WHY? The nuclear charge (# of p+

inside the nucleus) increases. This increase in positive charge pulls the e- cloud closer to the nucleus; therefore decreasing the atomic radius!

IONIC RADIUS: ANIONS: (- charge) become LARGER

than the parent neutral atom. They are gaining electrons, the e- spread out a little making the ion formed a little larger. [NONMETALS]

CATIONS: (+ charge) become SMALLER than the parent neutral atom. They are losing electrons from the valence shell. [METALS]

IONIC RADII

Anions: Get Larger

Cations: Get Smaller

METALLIC CHARACTERRemember where metals and nonmetals are located on the periodic table. That makes this trend one of the easiest to remember!

THE TREND

IONIZATION ENERGY What is that??? It is the energy required to remove the most loosely held electron from the valence shell of the atom in the gaseous phase.

Abbreviated IE

IE’S TRENDWithin a PERIOD, the IE increases with atomic #. The larger the atomic #, the larger the positive charge in the nucleus which means a stronger hold on the e-s; more energy to remove it.Within a GROUP, the IE decreases as you go down the group. Electrons are further away from the nucleus AND the shielding effect.

IONIZATION ENERGY’S TREND

ELECTRONEGATIVITY What is it??? It is a measure of the ability of an atom

to attract electrons to itself. Arbitrary scale - values range from 0.7

to 4.0 Fluorine has the highest

electronegativity (4.0). Noble gases are excluded since they

are already stable and don’t want to attract any electrons.

ELECTRONEGATIVITY TREND FOXY Fluorin

e!

FREAKY Franciu

m

TRENDS SUMMARY

Atomic radiusMetallic character

INCREASES

INCR

EASE

S

INCREASESINCREASES

Ionization EnergyElectronegativity

THAT’S ALL FOLKS!!