Please enable JavaScript.

Coggle requires JavaScript to display documents.

Chemistry - Coggle Diagram

- - - - Proposed By J.J. Thomson in 1904
      - Suggested that Atoms were made of positively charged "Pudding" and Negatively charged "Plums" embedded in it.
    - - He directed a beam of Alpha particles (+) at a thin sheet of gold foil and detected them using a fluorescent screen
      - The alpha particles should have passed through the foil with only slight deflections, however they did not and some even bounced back in the opposing direction.
        
        This proved that the Plum Pudding Model was wrong and that the nucleus exists, most of the atom is empty space and electrons are outside the nucleus
    - - Mendeleev left gaps in the periodic table because he predicted the existence of undiscovered elements and left gaps for them.
  - - - Reactivity increases down group 1
      - Outer electron is further from the nucleus, so it’s lost more easily.
    - - Reactivity decreases down group 7.
      - Harder to gain an extra electron because outer shell is further from the nucleus.
    - - Noble Gases
      - Very unreactive
      - Full outer shell of electrons
      - Low boiling point