eli5:Why is flourine not as dominant as Oxygen in earths rocks and minerals even though it is a better electron acceptor?

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It’s just rare. Oxygen is formed in huge quantities in large stars as a fusion product and is the third most abundant element in the galaxy. Fluorine is produced only through more unusual pathways, so it sits down in the 20s somewhere. It is actually more abundant in the earth’s crust than its concentration among the stars would suggest, probably because it is so furiously reactive and difficult to drive off.


I’ve got two books I think you’ll find interesting: Oxygen by Nick Lane and Symphony in C, Carbon and the Evolution of (almost) Everything by Robert M. Haven. The former will address some of the displacement of Oxygen through biological processes, the latter is simply mind altering.


There are several reasons, but the principal one is because of the way that the elements form in stars favors even numbered elements over the odd numbered ones, so even at time of creation of the elements, there was a lot more oxygen than fluorine. In terms of original abundance (if you accept the science on this, which I do for the most part), fluorine was about the same proportion as that of copper (a much larger element), and this is simply due to the way that elements are created during fusion (a lot of fusion is addition of “helium” (2 protons) nuclei, so adding 1 proton is much less likely. On top of that, of course, is that carbon (the reaction of 3 heliums into one atom; the triple alpha process) is a really favorable reaction, and oxygen is just the addition of He to C, so oxygen is almost as common as carbon.


Fluorine has a more complex structure. More protons, neutrons, and electrons all formed together in a organized way. The universe HATES organization so we get less and less of an element the more complex it is. That’s true on a universal scale. Idk about the earth specifically