Group 7 - Halogens

• What happens to the boiling point as we go down the group and why?

  increase van de walla increasedue to size and mass
• what happens to the electro negativity


  decrease as atoms
• What happens to the reactivity as we go down the group

  Reactivity decreases as they become less oxidant e cause they increase in size
• What is a displacement reaction?


  A more reactive halogen will displace a less reactive halide ion
• If you were to add cl2 to potassium chloride solution what would u expect to happen

  No reaction
• If you were to add cl2 to potassium bromide solution what would u expect to happen

  Chlorine to displace bromide forming 2cm3- ions and br2 orange solution
• If you were to add cl2 to potassium iodide what would u expect to happen

  Chlorine to displace iodide ions becoming 2Cl- and I2 Forming a brown solution
• What would happen if you were to add br2 to potassium iodide solution

  Bromide would displace the diced ions forming 2br- and I2 with brown solution forming
• What is the equation for bleach

  CL2 +2NOH —> NACLO + NACL +H20
• Why is bleach a displacement reaction

  Cl is being displaced and oxidised simutionesly
• What are some uses of bleach

  Treat waterCleaning agents
• State the trend in electrongetaivty of the elements in group 7. Explain this trend

  DecreaseAtoms gets bigger weaker attraction between outer electrons and ulcerous more shielding
• State the trend in reducing ability of the halide ions don group 7

  Increase
• Give an example of a reagent which could be used to show the reducing ability of bromide ions is different then hat of chlorine

  H2SO4
• In reference to electrons what os the term reduction and reducing agent

  Reduction is gain of electrons Reducing agent is donating electrons
• Iodine ions can reduce sulphuric acid tot three differnt products. Name three reduction products

  S2H2SS
• What observation can be made with teh reaction of bromide ions with chlorine gas

  Observation = orange solution 2br- + cl2 —> 2Cl- +br2
• Sodium bromide reacts with concentrated soulful acid in a different way then sodium chloride. Write an equation for the reaction and explain why bromide ions react differently from chloride ions

  2nabr + 2h2so4 -> br2 + na2so4 +so2+2h20