group 7- The Halogens

• Fluorine- pale green gas

  chlorine- green/yellow gas

  bromine- orange liquid

  iodine- grey/black solid, purple vapour

  Astatine

  mp &bp decrease

  density increases- atoms get closer together

  reactivity decrease- outer shell gets further, difficult to gain 1 electro to complete shell
• displacement reactions

  a halogen high up in group 7 will displace one lower than it within the group

  e.g chlorine will displace bromine
• reaction w iron wool

  done in a fume cupboard cus gases are toxic

  fluorine- reacts instantly w warm iron wool

  chlorine- reacts quickly w heated iron wool

  bromine- reacts slowly w heated iron wool

  iodine- reacts very slowly with strongly heated iron wool