Boric Acid as a Weak Monobasic Acid - Is it Really?

[anigeo]

how can boric acid be a weak monobasic acid?i thought it was tribasic.

 

[Ygggdrasil]

According to Wikipedia:

Boric acid does not dissociate in aqueous solution as a Brønsted acid, but is a Lewis acid which interacts with water molecules to form the tetrahydroxyborate ion, as confirmed by Raman spectroscopy:

B(OH)₃ + H₂O <--> B(OH)₄⁻ + H⁺

https://en.wikipedia.org/wiki/Boric_acid

 

[Borek]

To make things more complicated many sources list three dissociation constants for H₃BO₃ (which can mean it is able to react with another two water molecules in the same manner).