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What is the equation of the reaction between H3BO3(aq) with NaOH(aq)? Could reacting H3BO3(aq) with NaOH(aq) get its conjugate base H2BO3-(aq) and if so what is the balanced equation? Also is that the correct conjugate base? Thanks.

Dear Sir. Concerning your question about the reaction of boric acid with sodium hydroxide. Boric acid reacts with sodium hydroxide to produce sodium tetraborate and water according to the following equation: 4 H3BO3 + 2 NaOH → Na2B4O7 + 7 H2O Boric acid H3BO3 is weak acid and its reaction with sodium hydroxide can be carried out by the addition of excess of mannitol. Mannityl boric acid complex formed is strong acid and the equation as follows: 4 H3BO3 + 2 NaOH

mannitol → Na2B4O7 + 7 H2O

For more information you can visit the following link which may help you: http://copharm.uobaghdad.edu.iq/uploads/year%202013-2014/chem.lab3rd/7.%20Assay%20ob%20borax.pdf Thanks

There is nothing like H2BO3-. It is B(OH)4-, actually. H3BO3 is monoprotic acid. I believe the reaction between them is NaOH + H3BO3 → NaB(OH)4. B(OH)3 has a similar structure as Al(OH)3. We know Al(OH)3+NaOH → NaAlO2 + 2H2O. For Isam's suggestion, I think it might be due to the lack of NaOH. Na2B4O7 can be written as (2NaAlO2 + 2B(OH)3 - 3H2O). I worked on the determination of boric acid using base introduction technique and conductometric detection (see my publications). The ratio between B(OH)3 and NaOH is 1:1.

2 years ago Keith G Inman Paragon Bioservices My experience using boric acid to buffer pH says that Isam is correct. The equation he gives represents the stoichiometry used in my buffer calculations, with the buffering capacity of 100 mM H3BO3 being 50 mM against base (including initial pH adjustment). A quick titration would confirm this, but I had none on the shelf. Instead, I titrated HCl against Na2B4O7 and found the equivalence point at a ratio of 1:2 B4O7(2-) to HCl. This would seem obvious based on charge, and for this to settle the issue regarding H3BO3, we have to believe (which I do) Isam's equation correctly represents its neutralization.

(Base is a proton acceptor) (Acid is a proton donor) pH :- The pH is a measure of the concentration of hydrogen ions in an aqueous

solution pKa :- pKa (acid dissociation constant) is related, but more specific, in that it helps

you predict what a molecule will do at a specific pH. Essentially, pKa tells you what the pH needs to be in order for a chemical species to donate or accept a proton

pH and pKa

Once you have pH or pKa values, you know certain things about a solution and how it compares with other solutions: 

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The lower the pH, the higher the concentration of hydrogen ions, [H+]. The lower the pKa, the stronger the acid and the greater its ability to donate protons. pH depends on the concentration of the solution. This is important because it means a weak acid could actually have a lower pH than a diluted strong acid. For example, concentrated vinegar (acetic acid, which is a weak acid) could have a lower pH than a dilute solution of hydrochloric acid (a strong acid). On the other hand, the pKa value is a constant for each type of molecule. It is unaffected by concentration. Even a chemical ordinarily considered a base can have a pKa value because the terms "acids" and "bases" simply refer to whether a species will give up protons (acid) or remove them (base). For example, if you have a base Y with a pKa of 13, it will accept protons and form YH, but when the pH exceeds 13, YH will be deprotonated and become Y. Because Y removes protons at a pH greater than the pH of neutral water(7), it is considered a base.