group 7

• What group of the periodic table do halogens belong to?

  Group 7
• What are the physical states of the halogens at room temperature?

  Fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid.
• What is the electron configuration of fluorine?

  1s² 2s² 2p⁵
• What is the electron configuration of chlorine?

  1s² 2s² 2p⁶ 3s² 3p⁵
• What is the physical state and color of bromine at room temperature?

  Bromine is a browny-orange liquid.
• What is the physical state and color of iodine at room temperature?

  Iodine is a gray solid.
• How do boiling points change as you move down the group of halogens?

  The boiling points increase as you go down the group.
• Why do boiling points increase down the group of halogens?

  Because the size of the atoms and molecules increases, leading to larger van der Waals forces.
• What happens to electronegativity as you move down the group of halogens?

  Electronegativity decreases as you go down the group.
• Why does electronegativity decrease down the group of halogens?

  Because the atoms get larger, increasing the distance between the nucleus and bonding electrons, and there is more shielding.
• What is the fundamental rule regarding the reactivity of halogens in displacement reactions?

  • More reactive halogens will displace less reactive halide ions.
  • Reactivity decreases as you go down group 7.
• What is formed when chlorine reacts with bromide ions?

  Chlorine displaces bromide ions to form bromine and chloride ions.
• What color solution is formed when chlorine reacts with bromide ions?

  An orange solution is formed.
• What happens when chlorine reacts with iodide ions?

  Chlorine displaces iodide ions to form iodine and chloride ions.
• What color solution is formed when chlorine reacts with iodide ions?

  A brown solution is formed.
• What is the result when bromine reacts with chloride ions?

  No reaction occurs because bromine is less reactive than chloride ions.
• What is the result when bromine reacts with iodide ions?

  Bromine displaces iodide ions to form iodine and bromide ions.
• What is bleach made from?

  Bleach is made by mixing chlorine with sodium hydroxide.
• What type of reaction is used to produce bleach?

  A disproportionation reaction.
• What is the oxidation state of chlorine in bleach?

  Chlorine has an oxidation state of +1 in bleach.
• What is the purpose of adding chlorine to water?

  To kill bacteria and prevent waterborne diseases.
• What happens to chlorinated water when exposed to sunlight?

  Sunlight can decompose chlorinated water, reducing its effectiveness in killing bacteria.
• What are the advantages and disadvantages of chlorinating water?

  Advantages:

  • Destroys microorganisms that cause disease.
  • Long-lasting, reducing bacteria buildup.
  • Reduces growth of algae.

  
  

  Disadvantages:

  • Chlorine is toxic and can irritate the respiratory system.
  • Can cause severe chemical burns.
  • Potential formation of chloroform linked to cancer.
• What makes halide ions good reducing agents?

  Halide ions lose an extra electron, making them good reducing agents.
• What happens to the ionic radius of halide ions as you go down the group?

  The ionic radius increases as you go down the group.
• What is the result of halide ions reacting with concentrated sulfuric acid?

  Some halide ions can reduce concentrated sulfuric acid, producing various products.
• What is the oxidation state of sulfur in concentrated sulfuric acid?

  The oxidation state of sulfur in concentrated sulfuric acid is +6.
• What is the relationship between the size of halide ions and their ability to act as reducing agents?

  As the size of halide ions increases, their ability to act as reducing agents improves.
• What is the trend in reactivity of halogens as you move down the group?

  Reactivity decreases as you go down the group.
• What is the significance of knowing half equations in displacement reactions?

  Half equations help to understand the electron transfer in redox reactions.
• What is the role of sodium hydroxide in the production of bleach?

  Sodium hydroxide reacts with chlorine to produce sodium chlorate(I), which is bleach.
• What is the effect of chlorine on the growth of algae in water supplies?

  Chlorine reduces the growth of algae that can discolor water and affect its taste.
• Why is it important to regularly replace chemicals in swimming pools?

  Regular replacement is necessary because sunlight can decompose the chemicals, reducing their effectiveness.
• What is the relationship between the oxidation state of chlorine and its role in disproportionation reactions?

  In disproportionation reactions, chlorine is simultaneously oxidized and reduced, changing its oxidation state.
• What is the significance of the chlorine oxidation state of +1 in bleach?

  The +1 oxidation state indicates that chlorine is being oxidized in the formation of bleach.
• How does the presence of organic compounds in water affect chlorination?

  Organic compounds can react with chlorine to form potentially harmful byproducts like chloroform.
• What is the primary reason for chlorinating drinking water?

  The primary reason is to kill harmful microorganisms and prevent disease outbreaks.
• What is the relationship between the ionic radius of halide ions and their reducing ability?

  A larger ionic radius generally indicates a stronger reducing ability among halide ions.
• What is the significance of the oxidation state of sulfur in the context of halide reactions with sulfuric acid?

  The oxidation state of sulfur changes during the reaction, indicating the reduction of sulfur from +6 to lower states.
• What is produced when sodium chloride reacts with sulfuric acid?

  Hydrochloric acid and sodium hydrogen sulfate