Inspired by this question, I'm wondering why arsenous acid is frequently denoted $\ce{H3AsO3}$, as opposed to $\ce{As(OH)3}$, which would appear to more accurately reflect its connectivity?
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I feel like such a doofus, forgetting about sulfuric acid ($\ce{H2SO4}$), phosphoric acid ($\ce{H3PO4}$), and boric acid ($\ce{B(OH)3}$), etc. Great discussion, people!