Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Basicity of Halogen Ions - Point Out My Error

  1. Nov 13, 2011 #1
    This isn't technically a homework problem; I'm reading about Sn2 reactions and the basicity of halogen ions came up and for some reason I can't get my head around this Chem I concept.

    Please point out the flaw in this thinking:

    1) Fluorine (F) is a small, electronegative atom
    2) F will hold onto it's electrons super tightly
    3) Thus, it will less readily donate electrons.
    4) Conclusion: F is a sucky Lewis base.
    --PROBLEM: F- is a stronger base than I-.

    I KNOW that I can think about F- vs I- in terms of conjugate acids, or in terms of Bronsted-Lowry bases. I just want to know what's wrong with this thinking in particular, and why this thought process is leading me to the wrong conclusion.

    Much thanks! And no, I don't know why I'm making this simple concept harder for myself. But I know that on the test this will be my first thought progression and I WILL mess up if I don't figure out what's wrong with it.
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?