Paper 3

• What are group 1 metals

  Alkali metals
• What are group 7

  Halogens
• what are group 0

  Noble gases
• 2 properties of alkali metals?


  soft

  low melting points
• How does lithium react in water?

  Fizzes
• How does sodium react with water

  Melts into a ball and fizzes rapidly
• How does potassium react with water

  Gives off sparks and hydrogen given off burns with a lilac flame
• how does the reactivity of alkali metals change?

  increases going down
• Why does reactivity increase in alkali metals?

  Outer shells are further from nucleus, so the force of attraction is weaker so electrons are lost easier
• Chlorine at room temp

  Gas

  yellow-green
• Bromine at room temp


  Red-brown

  liquid
• Iodine at room temp

  Solid

  dark grey
• How does reactivity change in halogens

  Decrease going down
• Chemical test for chlorine

  Damp blue litmus paper

  +ve is red then white
• Chlorine reactions with metal

  Form ion, 1- charge
• Chlorine, bromine and iodine dissolve in water to form acidic solutions
• Chlorine displaces bromine and iodine
• predict astatine reaction with halide ions

  It will not displace them because it’s less reactive
• Halogen displacemnt reactions are redox because there is a movement of electrons
• Oxidation is loss
• Reduction is gain
• Chlorine + bromide ions -> bromine + chloride ions

  chlorine is reduced

  bromide if oxidised
• Why are group 0 gases inert

  Because their outer shells are full
• Noble gases increase in density going down the group
• Activation energy is the minimum energy needed to break the bonds of the reactants