Chemistry ☹️

• Halogens


  Group 7 of the periodic table
• Halogens


  • Boiling points increase as we go down the group
  • Physical state goes from gas at the top to solid at the bottom
• Atomic Radius

  This INCREASES down the Group since?


  • The number of electron shells increase

  • The shielding increases

  • The outer electrons are further from the nucleus

  • The outer electrons are less strongly attracted.
• Electronegativity

  This DECREASES down the Group since?

  • The number of electron shells increase

  • The shielding increases

  • The electrons in the covalent bond are further from the nucleus

  • The electrons in the covalent bond are less strongly attracted.
• Boiling-point

  This INCREASES down the Group since?

  • the atomic radius increases

  • the size of the molecules increases

  • the surface area increases

  • the strength of the van der Waal’s forces increases
• The oxidising power of the halogens DECREASES down the Gp since:?

  • The number of electron shells increase

  • The shielding increases

  • The ability to attract electrons from other atoms decreases
• What happens when a Cl2 halogen reacts with a CL- halide?

  No change
• What happens when a Cl2 halogen reacts with a Br- halide?

  Br2 is displaced because Cl2 has more oxidising power

  2Br-+Cl2 -> 2Cl- + Br2

  A yellow/brown solution is formed
• What happens when a Cl2 halogen reacts with a I- halide?

  I2 is displaced because Cl2 has more oxidising power

  2I-+Cl2 -> 2Cl- + I2

  A black/brown PPT is formed
• What happens when Br2 halogen reacts with Cl- halide?

  No change occurs, Cl2 is not displaced
• What happens when Br2 halogen reacts with Br- halide?

  No change occurs
• What happens when a Br2 halogen reacts with I- halide?

  I2 is displaced because Br2 has more oxidising power

  2i- + Br2 -> 2Br- + I2

  brown/black PPT formed
• What happens when an I2 halogen reacts with a Cl- halide?

  No change, Cl2 is not displaced
• WHAT HAPPENS WHEN halogen I2 reacts with halide Br-?

  No change, Br2 is not displaced
• What happens when I2 halogen reacts with I- Halide?

  There is no change