Trends in properties

Cards (34)

  • What type of molecules are halogens?
    Diatomic molecules
  • What is the physical appearance of fluorine?
    Pale yellow gas
  • What is the physical appearance of chlorine?
    Pale green gas
  • What is the physical appearance of bromine?
    Orange-brown liquid
  • What is the physical appearance of iodine?
    Dark purple/black solid
  • How does the color of halogens change down the group?
    The color gets darker as you go down
  • Why do halogens vary in color in different solvents?
    Due to different solubilities in solvents
  • Why do halogens dissolve better in non-polar solvents?
    Halogens are non-polar molecules
  • What type of agents are halogens?
    Good oxidising agents
  • How do halogens react as oxidising agents?
    By gaining electrons
  • How does the oxidising ability of halogens change down the group?
    It decreases going down the group
  • Why is fluorine a good oxidising agent?
    It has high electronegativity
  • What can be used to appreciate the different reactivities of halogens?
    Halogen displacement reactions
  • What are halide ions?
    Anionic form of a halogen
  • What role do halide ions play in reactions?
    They are reducing agents
  • How does the reducing ability of halide ions change down the group?
    It increases going down the group
  • Why does the reducing ability of halide ions increase down the group?
    Electrons are further from the nucleus
  • What can illustrate the reactions of halide ions with concentrated sulfuric acid?
    Oxidation and reduction reactions
  • What is the observation for bromine in reactions?
    Oxidised
  • What is the observation for sulfur in reactions?
    Reducer
  • Why is it important to learn observations for inorganic reactions?
    To back up theories with evidence
  • How can halide ions be tested?
    With silver nitrate
  • What is the basis of the test for halide ions?
    Silver halides are insoluble precipitates
  • What color precipitate does AgCl form?
    White precipitate
  • What color precipitate does AgBr form?
    Cream precipitate
  • What color precipitate does AgI form?
    Yellow precipitate
  • Why is it important to conduct carbonate and sulfate tests?
    To avoid false positive results
  • What are the equations for false positives in tests?
    AgCO3 and AgSO4 form white precipitates
  • What is the order of tests for halides, carbonates, and sulfates?
    1. Carbonate: Add acid
    2. Sulfate: Add barium chloride
    3. Halide: Add silver nitrate
  • How can ammonia be used to distinguish silver halides?
    Ammonia dissolves AgCl and AgBr
  • What happens to AgCl in dilute ammonia?
    It dissolves
  • What happens to AgBr in concentrated ammonia?
    It dissolves
  • What happens to AgI in ammonia?
    It is insoluble
  • How do all halogens exist in terms of their bonding?
    • All halogens exist as diatomic molecules.