Chemical bonds and types of bonding

• What are compounds?

  Substances in which 2 or more elements are chemically combined
• What are the three types of strong chemical bonds?

  Ionic, covalent, and metallic
• What characterizes ionic bonds?

  Particles are oppositely charged ions
• In which compounds do ionic bonds occur?

  In compounds formed from metals combined with non-metals
• What defines covalent bonds?

  Particles are atoms which share pairs of electrons
• Where do covalent bonds typically occur?

  In most non-metallic elements and in compounds of non-metals
• What is characteristic of metallic bonds?

  Particles are atoms which share delocalised electrons

  
• In which materials do metallic bonds occur?

  In metallic elements and alloys
• What happens to electrons in ionic bonding between a metal and a non-metal?

  Electrons in the outer shell of the metal atom are transferred
• What happens to metal atoms during ionic bonding?

  Metal atoms lose electrons to become positively charged ions
• What happens to non-metal atoms during ionic bonding?

  Non-metal atoms gain electrons to become negatively charged ions
• What is an ion?

  An atom that has lost or gained electron(s)
• Which groups of elements produce ions in ionic bonding?

  Metals in Groups 1 and 2 and non-metals in Groups 6 and 7
• What is the result of ion formation in terms of electron configuration?

  They gain a full outer shell of electrons, resembling a noble gas
• How can electron transfer during ionic compound formation be represented?

  By a dot and cross diagram

  
• What is the structure of ionic compounds?

  A giant structure of ions
• How are ionic compounds held together?

  By strong electrostatic forces of attraction between oppositely charged ions
• How does the 3D structure of ionic compounds affect the forces acting on them?

  The forces act in every direction
• Give an example of an ionic compound.

  Sodium chloride (salt)

  
• What is covalent bonding?

  When atoms share one or more pairs of electrons
• Name some small molecules that have strong covalent bonds.

  HCl, H2, O2, Cl2, NH3, CH4
• What are polymers in terms of covalent bonding?

  Large covalently bonded molecules
• What are giant covalent structures?

  Structures consisting of many atoms covalently bonded in a lattice structure
• Give examples of giant covalent structures.

  Diamond, silicon dioxide
• What characterizes metallic bonding?

  The bonding consists of positive ions and delocalised electrons arranged in a regular pattern

  
• What is the delocalised electron system in metallic bonding?

  The electrons ‘lost’ from the atoms to form positive ions

  
• What is the movement of delocalised electrons in metallic bonding?

  They are free to move through the structure

  
• Why are metallic bonds considered strong?

  Because delocalised electrons are shared through the structure