Chapter 7 86B

• Barium chloride

  Barium (Ba) and Chloride (Cl)
• Properties that characterize ionic compounds
• Ionic compound


  A compound formed by the transfer of electrons from a metal (positive ion) to a non-metal (negative ion)
• Formula


  A chemical symbol that identifies an element or compound
• Calcium fluoride


  Calcium (Ca) and Fluoride (F)
• Ionic compounds are neutral
• Properties of ionic compounds

  • Solid room temperature
  • High melting points
  • Conducts currents (only when molten or dissolved)
  • Neutral electrical charge
• Elements that will likely form ionic compounds

  Positive ions (metals) transfer electrons to negative ions (non-metals)
• Pairs of elements that will likely form ionic compounds

  • Cl, Br
  • Li, Cl
  • K, He
  • Na
• Cations

  Positive ions
• Ionic compounds conduct electric current when dissolved in water or molten because free moving charged particles (cations and anions) are free to migrate
• Electron configuration


  The arrangement of electrons in an atom or ion
• Anions


  Negative ions
• Many elements are more stable as ions than they are as atoms because ions achieve a noble-gas electron configuration