group 7 halogens

• What charge do halogens have when they gain an electron?

  Negative charge
• What is the trend in reactivity in group 7 as you go down the group?

  Reactivity decreases as you go down
• Why does reactivity decrease in larger atoms of group 7?

  Outermost electrons are further from nucleus
• What is Thompson’s model of the atom called?

  Plum pudding model
• What charge does an electron have?

  Negative charge
• What charge does a proton have?

  Positive charge
• What are the halogen displacement reactions?

  • More reactive halogen displaces less reactive halogen
  • Example: Chlorine displaces bromine
  • Example: Bromine displaces iodine
• What is the word equation for sodium bromide reacting with chlorine?

  Sodium bromide + chlorine → sodium chloride + bromine
• Why does chlorine displace bromine in the reaction with sodium bromide?

  Chlorine is more reactive than bromine
• Write the balanced symbol equation for sodium bromide reacting with chlorine.

  2NaBr + Cl₂ → 2NaCl + Br₂
• What is the rule for halogen displacement reactions?

  A more reactive halogen displaces a less reactive halogen
• What are the results of displacement reactions of halogens with sodium compounds?

  • Sodium chloride: No reaction with chlorine
  • Sodium bromide: Yellow/orange color of bromine appears
  • Sodium iodide: Brown color of iodine appears
• What color appears when bromine is added to cyclohexane?

  Yellow/orange color
• What color appears when iodine is added to cyclohexane?

  Brown color
• What is the true or false statement about group 7 being called alkali metals?

  False
• Is chlorine in group 7?

  True
• Will iodine displace fluorine?

  False
• Are all halogens gases at room temperature?

  False
• Will bromine displace chlorine?

  False
• What are the colors observed in halogen displacement reactions with sodium compounds?

  • Sodium chloride: No color change
  • Sodium bromide: Yellow/orange color
  • Sodium iodide: Brown color