C2

• What are ions?

  Charged particles made when electrons are transferred.
• How do metals form ions?

  Metals lose electrons to form positive ions.
• What charge do Group 1 metals form?

  1+
• How do non-metals form ions?

  Non-metals gain electrons to form negative ions.
• What charge do Group 6 non-metals form?

  2−
• What charge do Group 7 non-metals form?

  1−
• What is ionic bonding?

  The electrostatic attraction between oppositely charged ions.
• Between which types of ions does ionic bonding occur?

  Between positive metal ions and negative non-metal ions.
• What is the formula for sodium chloride?

  NaCl
• What is the electronic structure of a sodium atom?

  2,8,1
• What is the electronic structure of a chloride ion?

  2,8,8
• What do dot-cross diagrams not show?

  They don't show compound structure, size, or arrangement of ions.
• What are the three properties of ionic compounds?

  1. Giant ionic lattice structure with electrostatic forces acting in all directions.
  2. High melting and boiling points due to strong bonds.
  3. Conduct electricity only when molten or dissolved.
• What is a limitation of the ionic lattice model?

  The model is not to scale and does not show gaps between ions.
• Why do ionic compounds have high melting and boiling points?

  Because lots of energy is needed to overcome the many strong bonds.
• When do ionic compounds conduct electricity?

  Only when molten or dissolved, as ions are free to move.
• What is a covalent bond?

  A shared pair of electrons between two non-metal atoms.
• In which types of compounds does covalent bonding occur?

  In non-metal compounds and non-metal elements.
• What does a molecular formula show?

  How many atoms of each element are in a compound.
• What do dot and cross diagrams not show?

  They don't show relative sizes of atoms or their arrangement in space.
• What do ball and stick diagrams not show?

  They don't show 3D structure or the sizes of atoms.
• What are the properties of simple molecular substances?

  1. Low melting and boiling points; mostly gases or liquids at room temperature.
  2. Don't conduct electricity; no charged particles to carry charge.
• What are polymers?

  Very long chains of repeating units.
• Why are polymers usually solid at room temperature?

  Because they have relatively strong intermolecular forces.
• What are giant covalent structures?

  Solids containing atoms bonded to each other by strong covalent bonds.
• What is the melting and boiling point of giant covalent structures?

  High, as lots of energy is needed to overcome strong covalent bonds.
• Why don't giant covalent structures conduct electricity?

  Because there are no charged particles to carry charge.
• What are examples of giant covalent structures?

  Diamond, graphite, and silicon dioxide (silica).
• What are the properties of diamond?

  Very hard, with a high melting point and does not conduct electricity.
• What are the properties of graphite?

  Soft, slippery, conducts electricity and thermal energy.
• What are fullerenes?

  Hollow shapes made of carbon atoms, often in rings.
• What is Buckminsterfullerene (C₆₀)?

  A spherical fullerene and the first to be discovered.
• What are nanotubes used for?

  Used in nanotechnology, electronics, and materials.
• What is metallic bonding?

  Strong electrostatic attraction between metal atoms and delocalised electrons.
• What are the four properties of metals?

  1. High melting and boiling points.
  2. Good thermal conductors.
  3. Good electrical conductors.
  4. Soft and malleable.
• Why are alloys harder than pure metals?

  Because new elements distort layers of metal atoms, preventing them from sliding past each other.
• What does particle theory explain about solids, liquids, and gases?

  • Solids: Regular arrangement, fixed position, very close together.
  • Liquids: Random arrangement, move around each other, close together.
  • Gases: Random arrangement, move quickly in all directions, far apart.
• What does particle theory not show?

  It doesn't show the forces between the particles.
• What are the changes of state and their processes?

  • Melting: Solid to liquid, particles gain energy.
  • Freezing: Liquid to solid, particles lose energy.
  • Boiling: Liquid to gas, particles gain energy.
  • Condensing: Gas to liquid, particles lose energy.
• What is the relationship between energy needed to change state and the strength of forces between particles?

  Stronger forces mean a higher melting and boiling point.