Chemistry

Chemistry

Reaction with concentrated Sulphuric acid
  * Sodium Chloride
      *
  * Sodium Bromide
      *
      * then
      *
  * Sodium Iodide
      *
  * then
  *
Chlorine Water
  * Disproportionation – chlorine is simultaneously oxidised to a Cl- ion and reduced to a ClO- ion
      *
Trends in chemical properties
  * chlorine will displace bromine and iodine
  * bromine will displace iodine but not chlorine
  * iodine will displace neither chlorine or bromine
  * Oxidising Power
      *
  * Reactions with Cl2
      * Halide ion
        1. Br-
        2. I-
      * Observations
        3. yellow/brown
        4. brown colour, black ppt
      * Conclusion
        5. Br2 displaced
        6. I2 displaced
  * Reactions with Br2
      * Halide ion
        1. Cl-
        2. I-
      * Observations
        3. no change
        4. brown colour, black ppt
      * Conclusion
        5. Cl2 not displaced
        6. I2 displaced
  * Reactions with I2
      * Halide ion
        1. Cl-
        2. Br-
      * Observations
        3. no change
        4. no change
      * Conclusion
        5. Cl2 not displaced
        6. Br2 not displaced
Trend in electronegativity
  * decreases as atomic number increases
      * Because
      * Atomic number increases
      * attraction for bonding electron pair in covalent bond increase
      * increase number of electron shells
      * shielding increases
      * electrons less strongly attracted
      * atomic radius increases
Trend in boiling point
  * all exist as diatomic molecules
  * attraction = weak intermolecular forces
  * van der Waals forces
  * increase with size of molecule
Tests
  * Tests for halide ions
  * Reagents
      * Silver nitrate solution
        * Fluoride ions
            * Silver fluoride is soluble
            * no ppt formed
        *...