Bonding, structure and the properties of matter

• What are the three states of matter?

  Solids, liquids, and gases
• What are the properties of solids?


  • Fixed shape and volume
  • Cannot be easily compressed
  • Expand slightly when heated
• What are the properties of liquids?

  • Fixed volume but changes shape in different containers
  • Cannot be easily compressed
  • Boil and then evaporate when heated
• What are the properties of gases?

  • No fixed volume and no fixed shape
  • Can be easily compressed
  • Expand or increase pressure when heated
• What does particle theory explain?

  It explains the properties of the three states of matter.
• What are the characteristics of particles in solids?

  • Strong forces of attraction
  • Closely packed together
  • Vibrate around fixed positions
• What are the characteristics of particles in liquids?

  • Strong forces of attraction
  • Close together but can slide over each other
  • Move in random motion
• What are the characteristics of particles in gases?

  • Very weak forces of attraction
  • Far apart
  • Move at high speeds in random motion
• What are the limitations of the particle model?

  • Particles are not solid spheres
  • Particles vary in size and shape
  • Particles can change shape due to forces of attraction
• What happens when a solid is heated?

  1. Particles gain energy
  2. Vibrate more, weakening forces
  3. At a certain temperature, particles break free (melting)
• What happens when a liquid is heated?

  1. Particles gain more energy
  2. Move faster, weakening bonds
  3. At a certain temperature, particles break bonds (evaporating)
• What are physical changes in states of matter?

  • Do not change the particles
  • Change only their arrangement or energy
• What are the two types of strong chemical bonding?

  Ionic bonding and covalent bonding
• What is ionic bonding?

  • Electrostatic forces of attraction between oppositely charged ions
  • Involves transfer of electrons from metal to non-metal
• What is covalent bonding?

  • Non-metals share electrons to fill their outer shell
  • Form molecules through shared pairs of electrons
• What are the properties of ionic compounds?

  • High melting and boiling points
  • Do not conduct electricity when solid
  • Conduct electricity when melted or dissolved in water
• What are the properties of small (simple) molecules?

  • Usually gases or liquids
  • Low melting and boiling points
  • Do not conduct electricity
• What are the properties of giant covalent structures?

  • Very high melting points
  • Atoms linked by strong covalent bonds
  • Do not conduct electricity (except graphite)
• What is the structure of diamond?

  • Each carbon atom forms four covalent bonds
  • Creates a giant covalent structure with a tetrahedral shape
  • Very high melting point and strong
• What is the structure of graphite?

  • Each carbon atom forms three covalent bonds
  • Forms layers of hexagonal rings
  • Good conductor of electricity due to delocalised electrons
• What is graphene?

  • One layer of graphite
  • Thin, flexible, and strong
  • Can conduct electricity
• What are fullerenes?

  • Molecules of carbon shaped like tubes or balls
  • Can be used for drug delivery and as catalysts
  • Have a huge surface area
• What are the properties of metals?

  • High melting and boiling points
  • Malleable and ductile
  • Conduct electricity and heat
• What are the properties of alloys?

  • Mixture of two or more elements, at least one being a metal
  • Harder than pure metals
  • Atoms are not able to slip past each other easily
• What are nanoparticles?

  • Structures that are ≤100nm in size
  • Have a very high surface area to volume ratio
  • May have different properties than bulk materials
• What are some uses of nanoparticles?

  • New catalysts
  • Improve electric circuits
  • Enhance cosmetics and nanomedicine
• What are the concerns regarding nanoparticles?

  • Long-term health effects are unknown
  • Potential to damage cells if they enter the body
  • Environmental impact when washed away
• What is the surface area to volume ratio formula?

  Surface area to volume ratio = Surface area / volume
• If the size of a cube decreases by a factor of 10, what happens to the surface area to volume ratio?

  It increases by a factor of 10.
• How do the properties of nanoparticles differ from bulk materials?

  Nanoparticles may have different properties due to their high surface area to volume ratio.
• What is nanotechnology?

  Technology that uses very small particles like nanotubes.
• What is the first fullerene to be discovered?

  Buckminsterfullerene (C₆₀)
• What is the role of silver nanoparticles in medicine?

  They have antibacterial properties and can be used in surgical masks and dressings.
• How does the structure of graphene contribute to its properties?

  Graphene is strong, light, and can conduct electricity due to delocalised electrons.
• What is the significance of the delocalised electrons in metals?


  They allow metals to conduct electricity and heat.
• Why are alloys harder than pure metals?

  Alloys have different sized atoms that disrupt the layers, preventing them from slipping past each other.
• What is the structure of a giant metallic lattice?

  It consists of positive metal ions surrounded by delocalised electrons.
• What happens to the properties of materials at the nanoscale?

  They may exhibit different properties compared to the same materials in bulk form.
• What is the effect of the high surface area to volume ratio in nanoparticles?

  It allows for more effective reactions and interactions with other substances.
• What is the role of weak intermolecular forces in fullerenes?


  They allow fullerenes to slide over one another, making them good lubricants.