I want to create a locale (hopefully a whole planet?), where the ocean is breathable. I was looking at perfluorocarbons, so the liquid part is at least possible(?)
Is there any way to create a world where the oceans might be like a natural version of perfluorocarbon or some other naturally occurring breathable liquid for humans?
I know that breathing the liquid is hard for the lungs to circulate in and out (and hypercapnia is an issue), but for now let’s focus on the environment. Thank you.
Edit: How about with a little handwavium?