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Group 7 - Coggle Diagram

- - - - why?
        
        Because going down the group the group there are more shells because there are more electrons
  - - - Why?
        
        Atomic radius increases thus making it harder to attract electrons to the positive charge of the nucleus which is also weakened with shielding
  - - - Why?
        
        Because the atomic radius is greater and there is more shielding down the group
  - - - Why?
        
        Because group 7 elements are simple covalent molecules held by VDW forces. Strength of IMF inxreases as Ar increases thus the strength of the VDW forces increases down group meaning more energy is needed to covercome it.
  - - - Decreases down group
        
        Because their ability to attract electron decreases due to shielding and a larger atomic radius
  - - - Br-: forms ppt, does not dissolve in dilute in dilute ammonia but dissolves in concentrated ammonia
        
        I-: forms a yellow ppt and does not dissolve in concentrated ammonia
- - - - Br-: forms ppt, does not dissolve in dilute in dilute ammonia but dissolves in concentrated ammonia
        
        I-: forms a yellow ppt and does not dissolve in concentrated ammonia
  - - - Tested for by using BaCl2 to form a white ppt
    - - Ions indicate the substance is alkaline thus can be identified with red litmus paper, that turns red to blue
    - - When acid like HCl is added, carbonate ions will fizz and CO2 gas is given off. Gas can be collect and bubble in limewater which turns cloudy
  - - - Ca2+: Brick red
        
        Sr2+: Red
        
        Ba2+: Pale green
    - - If NH4+ ions are present, ammonium gas is given off thus can be tested using red litmus paper. Should turn blue if present