Ionic Bonds

What are Ionic Bonds?

  • Ionic bonds are formed when electrons are transferred from a metal atom to a non-metal atom.
  • The metal atom loses electrons to become a positively charged ion called a cation.
  • The non-metal atom gains electrons to become a negatively charged ion called an anion.
  • These oppositely charged ions are then attracted to each other, forming an ionic bond.

Properties of Ionic Compounds

  • Ionic compounds form crystalline structures known as giant ionic lattices.
  • They often have high melting and boiling points due to the strong electrostatic forces between ions.
  • Ionic substances are usually soluble in water, but insoluble in non-polar solvents.
  • When dissolved in water or melted, ionic substances conduct electricity as the ions become free to move and carry charges.

Examples of Ionic Compounds

  • Sodium Chloride (NaCl): Sodium loses 1 electron to become a +1 cation, and chlorine gains this electron to become a -1 anion. They come together to form an ionic bond in sodium chloride.
  • Calcium Oxide (CaO): Calcium loses 2 electrons to become a +2 cation and oxygen gains these 2 electrons to become a -2 anion. They come together to form an ionic bond in calcium oxide.

It’s important to draw the dot-and-cross diagrams for these compounds to fully understand ionic bonding.

Key Points of Understanding

  • Understand the process of electron transfer in ionic bonding.
  • Know the properties of ionic compounds.
  • Be able to identify examples of ionic compounds and draw their dot-and-cross diagrams.