Halogens and Noble Gases

• What are the group seven elements known as?

  Halogens
• What are the group zero elements known as?

  Noble gases
• What are the properties of halogens?

  • Fluorine: poisonous yellow gas, very reactive
  • Chlorine: poisonous green gas, less reactive
  • Bromine: reddish-brown volatile liquid, poisonous
  • Iodine: dark gray solid, forms poisonous purple vapors, antiseptic
• What is the state of fluorine at room temperature?

  Poisonous yellow gas
• What is the state of chlorine at room temperature?

  Poisonous green gas
• What is the state of bromine at room temperature?

  Reddish-brown volatile liquid
• What is the state of iodine at room temperature?

  Dark gray solid
• What do halogens form when they exist as pairs of atoms?

  Diatomic molecules
• How do halogens form diatomic molecules?

  By sharing electrons and forming covalent bonds
• What type of structures do halogen compounds form with non-metals?

  Simple molecular structures
• What happens to the melting and boiling points of halogens as you go down the group?

  They increase
• How does reactivity change among halogens as you go down the group?

  Reactivity decreases
• Why does reactivity decrease in halogens down the group?

  Outermost shell gets further from nucleus
• What do we call a halogen that gains an electron?

  Halide
• What are the names of halides formed from halogens?

  Fluoride, chloride, bromide, iodide
• With which metals do halogens most often form ionic compounds?

  Alkali metals
• What is a displacement reaction involving halogens?

  A more reactive halogen displaces a less reactive one
• What happens when chlorine gas is pumped into potassium bromide solution?

  Chlorine displaces bromine to form potassium chloride
• What are the characteristics of noble gases?

  • Colorless gases
  • Full outer shells (inert)
  • Exist as single atoms
  • Non-flammable
  • Boiling point increases down the group
• Why are noble gases considered inert?

  They have full outer shells
• How do the boiling points of noble gases change down the group?

  They increase
• What is the flammability of noble gases?

  Non-flammable
• What are the trends in properties for halogens and noble gases?

  Halogens:

  • Melting and boiling points increase down the group
  • Reactivity decreases down the group

  
  

  Noble gases:

  • Boiling point increases down the group
  • Inert due to full outer shells