Family of Metals and Periodic Trends Review

Vocabulary flashcards covering periodic trends (valence electrons, shielding, effective nuclear charge, radius reactivity) and the distinct properties of elemental families (alkali metals, alkaline earth metals, transition metals, halogens, noble gases, metals, metalloids, and non-metals).

Valence Electrons across a Period

• Elements in periods going from LEFT to RIGHT increase by 1 valence electron

Shielding across a Period

• Shielding same; principle energy level (added electron goes into valence shells)

$Z_{\text{eff}}$ across a Period

• Zeff increases; proton increase, inner shell same

Shielding down a Group

• Shielding Increases; More principal energy level occupied

$Z_{\text{eff}}$ down a Group

• Zeff constant; shielding electrons and proton increase at same rate

$Z_{\text{eff}}$ (Effective Nuclear Charge)

• Effective nuclear charge

• # protons - # inner shell electrons

Electron Shell Radius and Reactivity

• Bigger radius = more reactive

• Smaller radius = less reactive

Valence Electrons in Groups

• Elements in same group have the same # of electron in the outer shell (shared chemical properties)

Transition Metals

• Less reactive than alkaline earth metals

• Some very non-reactive

• Group numbers 3-12

Halogens

• MOST reactive NONMETALS

• Harder than alkali metals

• higher melting point than alkali metals

• Rarely found in elemental form

• Groups 12/7a

Alkaline Earth Metals

• Less reactive than alkali metals (still very reactive)

• Harder than alkali metals

• higher melting point than alkali metals

• Rarely found in elemental form

• Group 2

Alkali Metals

• Highly reactive (never found in nature in elemental form)

• Soft

• Low melting point

• React with water to make Alkaline solution

• Group number 1/1a

Noble Gases

• Unreactive

• Full set of valence electrons (STABLE, no need to gain/lose)

• Gaseous

• Group numbers, 18/8a 

Metals

• Conducts electricity

• Malleable (pressing)

• Solid at room temp

• High melting/boiling point

• Ductile (stretching)

Non-metals

• Not conductive of electricity (except for graphite)

• Brittle

• More varied in their properties (colors)

Metalloids

• Not conductive of energy (except for silicon)

• CAN be both malleable and brittle but depends on context

• Properties varied (pure, mixture, temp, element, conditions)

Location of Metals Non-Metals, and Metaloids

Locations of Alkaline Earth Metals, Halogens, Transition Metals, Alkali Metals, Noble Gases