Question

Whether boric acid is considered as protic acid? explain.

Answer 1

Boric acid:

• Boric acid is a monobasic acid with low strength. It can't emit ${\mathrm{H}}^{+}$ions on its own because it lacks the ability to do so.
• To complete its octet, it takes ${\mathrm{OH}}^{-}$ ions from water molecules and then releases ${\mathrm{H}}^{+}$ ions.
• $\mathrm{B}{\left(\mathrm{OH}\right)}_3\left(\mathrm{aq}\right)+2\mathrm{HOH}\left(\mathrm{aq}\right)\to [\mathrm{B}{\left(\mathrm{OH}\right)}_4{]}^{–}\left(\mathrm{aq}\right)+{\mathrm{H}}_3{\mathrm{O}}^{+}\left(\mathrm{aq}\right)$
  It is not a protic acid because it lacks hydrogen ions, but it is a Lewis acid because it can take electrons through ${\mathrm{OH}}^{-}$.
• As a result, we can rule out boric acid as a protic acid.