Group 7 - Physical Properties

• What do elements in the same group of the periodic table have in common?

  They have the same number of electrons in their outer shell
• What are the elements in group 7 of the periodic table called?

  Halogens
• What does the term 'halogen' mean?

  'Salt-producing' because they produce salts when reacting with metals
• What is the physical state of chlorine at room temperature?

  Gas
• What is the physical state of bromine at room temperature?

  Liquid
• What is the physical state of iodine at room temperature?

  Solid
• How do the melting and boiling points of halogens change down the group?

  The melting and boiling points increase as you go down the group
• What happens to the size of halogen molecules as you move down group 7?

  The molecules become larger
• What is the relationship between intermolecular forces and the melting and boiling points of halogens?

  Stronger intermolecular forces require more energy to overcome
• What is the predicted melting point of astatine?

  About 300°C
• What is the predicted boiling point of astatine?

  About 340°C
• What is the predicted state of astatine at room temperature?

  Solid
• What are the physical properties of halogens in group 7?

  • Chlorine: Pale green gas
  • Bromine: Brown liquid
  • Iodine: Purple-black solid
• What are the chemical properties of halogens?

  • React with metals to form salts
  • Exhibit trends in reactivity
  • Form acidic oxides
• What trends are observed in the physical properties of halogens as you move down group 7?

  • Increase in melting point
  • Increase in boiling point
  • Increase in molecular size
• What are the implications of stronger intermolecular forces in halogens?

  • Higher melting and boiling points
  • More energy required to change states
  • Larger molecular size contributes to stronger forces