group 7 CGP edexcel igcse

• What are the elements in Group 7 of the periodic table called?

  Halogens
• How do the properties of halogens change as atomic number increases?

  They have darker color and higher boiling point
• What is the physical state of chlorine at room temperature?


  Gas
• What color is bromine at room temperature?

  Red-brown
• What trend is observed in reactivity as you go up Group 7?

  The higher up, the more reactive the element
• What can you predict about astatine based on trends in Group 7?

  Astatine is a dark-colored solid
• How many electrons do all Group 7 elements have in their outer shell?

  7 electrons
• Why do halogens become less reactive down the group?

  It gets harder to attract the extra electron
• What happens in a displacement reaction involving halogens?

  A more reactive halogen displaces a less reactive one
• What is the result when chlorine is added to potassium iodide solution?

  Potassium chloride is formed, iodine is displaced
• What color change occurs when iodine is displaced in a reaction?

  The solution turns brown
• What is oxidation in terms of electron transfer?

  Loss of electrons
• What is reduction in terms of electron transfer?

  Gain of electrons
• What is a redox reaction?

  Reactions where oxidation and reduction occur simultaneously
• What is the role of chlorine in displacement reactions?

  Chlorine is an oxidizing agent
• What is the role of iodine in displacement reactions?

  Iodine is a reducing agent
• What are the properties of halogens in Group 7?

  • Atomic number increases down the group
  • Color changes from green (chlorine) to dark grey (iodine)
  • Physical state changes from gas (chlorine) to solid (iodine)
  • Boiling point increases from -34 °C (chlorine) to 185 °C (iodine)
• What are the trends in reactivity and properties of halogens?

  • Reactivity decreases down the group
  • Boiling point increases down the group
  • Color darkens down the group
• What happens during halogen displacement reactions?

  • More reactive halogen displaces less reactive halogen
  • Electrons are transferred between halogens
  • Oxidation and reduction occur simultaneously