Periodic table

Arrangement Mendeleev arranged the first periodic table. Arranged by increasing atomic mass. Periodic Law: arranged in order of increasing atomic number. Repetition of properties.

Arrangement Periods/Series: horizontal rows

Arrangement Groups/Families: vertical columns

Metals Physical Properties Chemical Properties Conductors Luster: reflects light Ductile Malleable Solids at room temperature Exception: Mercury High melting point Lose valence e- easily Low Electronegativity Corrode easily

Metals Alkali Metals React with water 1 ve-

Metals Alkaline earth Metals React with Halogens 2 ve-

Metals Transition Metals Many oxidation states Different number of ve-

Nonmetals Physical Properties Chemical Properties Mostly gas at room temperature. Some solids One liquid: Bromine Opposing properties to metals. Poor conductors. Exception: Carbon Gain or share ve- High electronegativity

Nonmetals Halogens Form salts Form acids when bonded to Hydrogen 7 ve-

Nonmetals Noble Gases Unreactive/inert Odorless and colorless 8 ve-

Metalloids Similar to both metals and nonmetals. Different conditions change properties. Form alloys with metals. Stairstep elements

Atomic Radii (AR) Measured from center of the nucleus to edge of the electron cloud. Increases down a group/family Adds energy levels Decreases across a period/series More p+ and e- increases the attraction, pulling electron cloud closer to the nucleus

Atomic Radius Practice Which of the following in each pair has a greater atomic radius? Lithium or rubidium Aluminum or chlorine Sodium or lead Magnesium or fluorine

Electronegativity (EN) Ability to gain or hold electrons A + e- A- + E Forms negative ions called anions Anion: negative “AN(t)ion” Does not include Noble Gases

Electronegativity (EN) Decreases down a group More energy levels More space for electrons to be lost Less energy to lose e- Increases across a period More e- in energy levels Held more tightly More energy needed to give up e-

Electronegativity Practice Which of the following in each pair has a lower electronegativity? potassium or arsenic Chlorine or Iodine calcium or fluorine Strontium or barium

Ionic Radii (IR) Opposite trend from atomic radii Decreases down a family Increases across a series Larger atoms lose e- to become cations Cation: positive “CATion” Smaller atoms gain e- to become anions Anion: negative “AN(t)ion”

Ionization Energy (IE) Energy to remove outer electrons (ve-) A + E A+ + e- Forms positive ions called cations Cation: positive “CATion”

Ionization Energy (IE) Decreases down a group More energy levels, electrons further from nucleus e- easier to remove, less energy needed Increases across a period More e- Held tighter to nucleus More energy to remove e-

Ionization Energy Practice Which element in the following pairs has the lowest Ionization Energy? Boron or Nitrogen Lithium or Neon Sodium or phosphorus Iodine or argon

Trends Practice Potassium or Hydrogen Sodium or Cesium Which element has the lowest of all four trends? The highest? Potassium or Hydrogen Sodium or Cesium Carbon or bromine Zinc or tin