H3BO3 is a weak monobasic acid or weak monoprotic acid? which is apt?

Question

anonymous · Answer

i know that it doesn't donate proton but accepts electron pair and hence its not a bronsted lowry acid but a lewis acid.

anonymous · Answer

monoprotiic is usu. used for base?
anything like that?

alphadxg · Answer

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a monobasic acid is an acid that is capable of giving one proton (H+ ion) in an acid-base reaction. 
A Lewis acid is a molecular entity that accepts an electron pair from another entity. 

Boric Acid is a Monobasic Lewis acid. 

The word "acid" in Boric acid (H3BO3) gives a wrong idea that Boric acid releases protons. Boric acid is not a Bronsted acid, but a Lewis acid (All Bronsted acids are Lewis acids, but the reverse is not always true), that is it accepts electrons and does not release protons. 
When H3BO3 is added to water, the following reaction takes place: 

H2O + H3BO3 -> B(OH)4- + H+

This clears up a lot of things. We see that Boric acid forms a borate ion, by accepting the electon-pair of OH-, thus justifying it being a Lewis acid. The second point is that a H+ ion is generated, which would be used up in an acid base reaction. Hence, it is monobasic too.