Periodic Table TrendsPeriodic Table Trends

Periodic Table Trends

Metallic character

Metallic Character

• Depends on how readily the element gives up their valence e-’s

Atomic Radius

Same shell across the periodAddition of one proton draws the electrons closer to the nucleus

Graph of Atomic Radius

Electronegativity

Electronegativity

• The tendency of an atom to attract e-’s

• Fluorine is the most electronegative element in the table

• WHY?– Its empty valence shell is near the highly

attractive (+) nucleus (note: has 9 protons)– No shielding effect from inner shells

Ionisation Energy

Ionisation Energy

• The amount of energy (kJ) required to remove the most loosely held e- from an atom to form a positive ion– Eg. K (g) K+ (g) + e- (IE = 500 kJ)

– Eg. Ne (g) Ne+ (g) + e- (IE = 2000 kJ)

– A higher IE would mean a higher attraction to the nucleus

Ionisation Energy

• Affected by:– Charge of the nucleus– Distance of the e- to the nucleus– The # of inner e- shells shielding or screening

the outer e-’s– If e- is single or paired within the orbital

Reactivity