Ionic bonding

• What diagrams will be used to explain ionic bonds?

  Dot and cross diagrams
• What are ions?

  Atoms that have lost or gained electrons
• How are ions formed?

  When atoms lose or gain electrons
• Why does a sodium atom form a positive ion?

  It needs to lose one electron
• What determines the stability of an atom?

  Having a full outer shell
• What ion does chlorine form?

  One minus chloride ion
• Why does chlorine form a negative ion?

  It needs to gain one electron
• What normally happens in real life instead of isolated reactions?

  Transfer of electrons from one atom to another
• What happens to atoms after an electron transfer?

  They become ions with full outer shells
• What is the significance of square brackets around ions in dot and cross diagrams?

  To show the charge of the ion
• What force attracts ions to each other?

  Electrostatic forces
• What is the electrostatic force between ions called?

  Ionic bond
• How strong are ionic bonds?

  Very strong, similar to covalent bonds
• What is the name of the diagram used to represent ionic compounds?

  Dot and cross diagram
• Why are electrons represented as dots and crosses?

  To distinguish electrons from different atoms
• What should be shown with an arrow in a dot and cross diagram?

  Movement of electrons
• Which electron shells are sometimes drawn in dot and cross diagrams?

  Outermost shell
• How many electrons does magnesium have in its outer shell?

  Two
• In forming magnesium chloride ($MgCl_2$), which atom loses electrons?


  Magnesium
• How many electrons does each chlorine atom need to complete its outer shell?

  One
• In the formation of $MgCl_2$, where do the electrons move from and to?


  From magnesium to chlorine
• What ions are formed in the reaction between magnesium and chlorine?

  Magnesium two plus and two chloride one minus
• How are ions arranged in dot and cross diagrams with more than two ions?

  As they would be in a real compound