Group 7 the Halogens

• What group of elements do halogens belong to?

  Group seven elements
• Which halogens are primarily dealt with in school?

  Chlorine, bromine, and iodine
• How are halogens typically represented in their molecular form?

  As diatomic molecules (e.g., Cl$_2$)
• What is the charge of halide ions?

  They have a single negative charge
• How are halide ions named?

  With the suffix "ide" (e.g., chloride)
• What is the formula for chloride, bromide, and iodide ions?

  Cl$^-$, Br$^-$, I$^-$
• What happens when chlorine is added to potassium bromide?

  Chlorine displaces bromine, producing an orange solution
• Why is potassium considered a spectator ion in the reaction?

  It does not participate in the reaction
• What color change occurs when chlorine reacts with bromide ions?

  An orange solution is produced
• What is the ionic equation for chlorine reacting with bromide ions?

  Cl$_2$ + 2Br$^-$ → Br$_2$ + 2Cl$^-$
• What type of reaction occurs when chlorine displaces bromine?

  It is a displacement reaction
• What is the role of chlorine in the displacement reaction with bromide?

  Chlorine acts as an oxidizing agent
• What happens to the oxidation state of chlorine in the reaction?

  Chlorine is reduced from 0 to -1
• What happens to the oxidation state of bromine in the reaction?

  Bromine is oxidized from -1 to 0
• What is the trend in oxidizing power among halogens?

  Oxidizing power decreases down the group
• What is produced when bromine reacts with iodide ions?

  Iodine is produced, resulting in a brown solution
• Why is chlorine a better oxidizing agent than iodine?

  Chlorine is smaller, attracting electrons better
• What is the ionic equation for bromine reacting with iodide ions?

  Br$_2$ + 2I$^-$ → 2Br$^-$ + I$_2$
• What is the significance of the size of halogen atoms in redox reactions?

  Smaller atoms are better at gaining electrons
• What is the main takeaway regarding halogens and their reactions?

  Learn the ionic equations and displacement reactions
• What are the key characteristics of halogens and halides?

  • Halogens are group seven elements
  • They exist as diatomic molecules (e.g., Cl$_2$)
  • Halides are negatively charged ions (e.g., Cl$^-$)
  • Chlorine, bromine, and iodine are the main halogens studied
  • Oxidizing power decreases down the group
• What are the types of reactions involving halogens?

  • Displacement reactions
  • Redox reactions
  • Ionic equations for reactions
  • Color changes during reactions
• What should students focus on when studying halogens?

  • Learn equations and reactions
  • Understand oxidation states
  • Memorize color changes
  • Practice ionic equations
• Why is one oxidizing agent better than another?

  It is less easily reduced.
• What does a better oxidizing agent do?

  It oxidizes all below it.
• What is the reaction that forms bleach?

  2 NaOH + Cl₂ → NaCl + NaClO + H₂O
• What is the chemical formula for bleach?

  NaClO
• What is the oxidation state of chlorine in NaClO?

  +1
• What is a disproportionation reaction?

  It involves a substance being both oxidized and reduced.
• What is the oxidation state of chlorine in Cl₂?

  0
• What is chloric acid classified as?

  A weak acid that partially ionizes.
• Why is chlorine used in water treatment despite being toxic?

  Its benefits outweigh the risks.
• What does chlorine do in water treatment?

  Kills bacteria to make water safe.
• What happens to the reducing power of halides down the group?

  It increases down the group.
• What is the relationship between ion size and reducing power?

  Larger ions are better reducing agents.
• What is the first reaction when sodium chloride reacts with sulfuric acid?

  Produces sodium hydrogen sulfate and hydrogen chloride.
• What color fumes are produced when sodium chloride reacts with sulfuric acid?

  Misty white fumes.
• What is the oxidation state of sulfur in sodium hydrogen sulfate?

  +6
• What is the reaction of sodium bromide with sulfuric acid?

  Produces sodium hydrogen sulfate and hydrogen bromide.
• What is the key point to remember about sodium fluoride's reaction with sulfuric acid?

  It produces misty white fumes of hydrogen fluoride.