Bonding

• IONIC BONDING-

  • Transfer of electrons between a metal and a non metal

  -Only the outer electrons are involved - e.g sodium (Na) only has one electron on its outer shell. This single electron is lost to the chlorine atom. The CI atom has one available space for an electron on its outer shell

  -The CI atom gains the electron from sodium (Na).

  -When Na loses an electron, the number of protons doesn't change. Therefore the Na becomes a positively charged ion (Na+)
• IONIC BONDING-

  • When CI gains an electron ,the number of protons doesn't change. Therefore the CI becomes a negatively charged ion. These charged ions are attracted to each other and form an ionic bond.
• Negative ions = Cation

  Positive ions = Anion

  Electrostatic Attraction= How ionic bonds form
• ION SIZE-

  • What happens to the size of the ion when you go down the periodic table ?


  -Generally, as you go down the periodic table, the ion size increases.
• ION SIZE-

  • When the ion is larger, the bond it produces is weaker
  • This is because the positive and negative ions are effectively further apart
  • The larger the charge on the ion, the stronger the ionic bonds that is produced
• COVALENT BONDING-

  • Consist of a shared pair of electrons
  • Forms between atoms of the same element, or between non- metals
  • We often show the outer shell only, for simplicity
• • Both atoms could reach a stable configuration if they shared electrons
  • This forms the covalent bonds
  • The shared pair of electrons is attracted to both nuclei

  (ATTATCH IMAGE)
• DATIVE BONDING-

  • A co-ordinate bond (also called a dative covalent bond) is a covalent bond in which both electrons come from the same atom.
• METALLIC BONDING-

  Properties of metals:

  • High melting points- transition metals (d block)
  • Low melting points -Group 1
  • They all conduct electricity
  • Form coloured compounds (transition metals only)
  • Variable reactivity (most reactive group 1)
  • All solids at room temperature. except mercury
  • They all conductors of heat
  • Malleable- hammered into shape and keeps its strength
  • Ductile- Drawn into wires