Paper 1

• What group do halogens belong to?

  Group 7
• What happens to the relative molecular mass as we go down group 7?

  It increases
• How do halogens form covalent compounds?

  By gaining electrons less easily
• What is the effect of greater distance between the nucleus and outer electron in halogens?

  It makes gaining electrons less easy
• What can a more reactive halogen do to a less reactive halogen?

  Displace it from its salt solution
• Why do elements react in ionic bonding?

  To achieve a full outer energy level
• What charge do Group 1 metals form when they lose an electron?

  1+ positive ion
• What charge do Group 7 non-metals form when they gain an electron?

  1- negative ion
• What do ionic compounds form?

  Crystals
• What is an ionic giant lattice?

  A structure with alternating positive and negative ions
• What holds the positive and negative ions in an ionic lattice together?

  Strong electrostatic forces of attraction
• Why do ionic compounds have high melting and boiling points?

  Due to strong electrostatic forces
• When can ionic compounds conduct electricity?

  When molten or in aqueous solution
• What is a covalent bond?

  A strong bond formed by shared electrons
• What are small covalent molecules at room temperature?

  Gases
• Why do small covalent molecules have low melting and boiling points?

  Due to weak intermolecular forces
• What happens to small covalent molecules as temperature increases?

  Molecular vibrations increase
• Why do small covalent molecules not conduct electricity?

  They have no overall electric charge
• What is diamond's structure?

  Giant covalent structure
• Why does diamond have a very high melting point?

  Due to strong covalent bonds
• Why can't diamond conduct electricity?

  It has no free electrons
• What is silicon dioxide made of?

  Silicon and oxygen
• What is a property of graphite?

  Good conductor of heat and electricity
• Why is graphite soft and slippery?

  Layers can slide over each other
• What are carbon nanotubes shaped like?

  Long cylinders
• What is a property of carbon nanotubes?

  High tensile strength
• What are polymers made from?

  Joining together thousands of monomers
• What type of bond do alkene monomers have?

  Double covalent bond
• Why are most polymers solid at room temperature?

  Due to strong intermolecular forces
• What is the structure of metals?

  Giant structure of atoms in layers
• What is metallic bonding?

  Attraction between delocalised electrons and positive ions
• Why are metals good conductors of heat and electricity?

  Due to delocalised electrons
• What is an alloy?

  A mixture of metals
• Why are alloys harder than pure metals?

  Different sizes of atoms disrupt layers
• What are the advantages and disadvantages of different bonding diagrams?

  • Dot and Cross:
  • Advantage: Clear electron source representation
  • Disadvantage: No shape information
  • 2D Stick:
  • Disadvantage: No electron source clarity
  • 3D Stick:
  • Advantage: Shows molecule shape
  • Ball and Stick:
  • Advantage: 3D ion visualization
  • Disadvantage: Misrepresents ion spacing
  • Space Filling:
  • Advantage: Shows ion packing
  • Disadvantage: Limited 3D visibility
• What happens in exothermic reactions?

  Energy is transferred to surroundings
• What occurs in endothermic reactions?

  Energy is taken in from surroundings
• What is the activation energy?

  Energy needed for particles to react
• What happens when a chemical bond is broken?

  It requires energy (endothermic)
• What happens when bonds are made?

  Energy is released (exothermic)