Paper 3

    Cards (56)

    • What is an element?

      A substance containing only one type of atom
    • What is the difference between a mixture and a compound
      A compound is a substance that contains two or more different types of atoms chemically bonded and a mixture consists of different substances which aren't chemically bonded
    • What is filtration?

      The separation technique which removes large insoluble particles from a liquid
      e.g sand from water
    • What is the process of evaporation and crystallisation?

      Leaves behind the solute, solvent is evaporated and dissolved substance is left and if heated gently crystallisation occurs
    • Define distillation
      Involves condensing the evaporated solvent and collecting it
    • What is fractional distillation?

      The process of separating two liquids due to their different boiling points
    • Chromatography
      process for separating components of a mixture
    • What is the mobile phase in chromatography?

      The solvent e.g water
    • What is the stationary phase in chromatography?

      The chromatography paper
    • Why is the starting line always drawn in pencil 

      So it won't move
      it is also just above the water line
    • How to calculate Rf value?

      distance substance moved/ distance mobile stage moved
    • Describe the arrangement of particles in a solid (3)

      -particles in regular arrangement
      -vibrate about fixed positions
      -cannot be compressed
    • describe the arrangement of particles in a liquid (3)

      • particles have no regular arrangement
      • particles are able to move past each other
      • cannot be compressed
    • Describe the arrangement of particles in a gas (3)
      • particles are far apart
      • move randomly at fast speeds
      • can be compressed
    • What did John Dalton think of matter?

      they were made of indivisible particles
    • Who created the plum pudding model?
      JJ Thomson
    • What did Rutherford discover and how?

      The nucleus is small and positively charged by finding most alpha particles went straight through the gold layer
    • What did Bohr discover?

      Electrons exist in shells
    • What did Chadwick determine?

      The nucleus contained NEUTRONS as well as protons
    • What is an atomic number?

      The number of protons present in the nucleus (smaller number)
    • What is the mass number?

      The amount of protons and neutrons present in the nucleus
    • Define an isotope
      The same element with different numbers of neutrons
    • Electron shells fill up:

      2,8,8,2
    • Group 1 (3)

      Alkali metals (1+)
      More reactive as you go down the group
      React with water to produce an alkali
    • Group 7 (4)

      Halogens (1- ions)
      Less reactive down the group
      Boiling point increases down the group
      non-metals
      accept 1 electron to achieve a full outer shell
    • Group 8/0 (2)
      Noble gases
      Very unreactive
    • What is special about transition metals?

      They can donate different numbers of electrons
    • What is metallic bonding?

      The strong electrostatic attraction between the sea of negative delocalised electrons and positive metal ions
    • Ionic Bonding
      When metal atoms donate electrons to non-metals to form ions
      Ionic bonding
      This process can be displayed through a dot and cross diagram
    • Why can ions only conduct electricity when molten or dissolved?

      Because the ions are free to move in there states, carrying charge
    • Ionic substances (3)

      high melting/ boiling points due to strong ionic bonds
      ion have strong electrostatic forces between them
      arranged in a lattice of repeating units of positive and negative ions
    • What are the names of positive ions and negative ions?
      positive ions are known as cations
      negative ions are known as anions
    • What is covalent bonding? (3)

      Non-metals bond to each other
      The atoms share electrons to achieve full outer shell
      They have low boiling points due to weak intermolecular forces that need to be overcome
    • Diamond (3)

      One of the hardest known substances due to very strong bonds
      Each carbon atom is joined to four other carbon atoms
      Giant covalent structure
    • All giant covalent structures have...

      very high melting points as you would have to break the covalent bonds
    • Graphite
      Delocalised electrons form weak bonds between layers
      Can conduct electricity as the electrons can move
      Layers can slide past each other
    • What is an allotrope?

      Structures made of the same element but arranged differently
    • Use of fullerenes/ nanotubes
      Used for electronics, medical purposes
    • What are moles used for?

      To compare quantities of substances
    • What is the relative formula mass?

      the sum of relative atomic masses of the atoms shown