Does Boric Acid Expire ? or become B2O3 after 5-10 years on its own?

[mubashirmansoor]

Does Boric Acid Expire ? or become B2O3 after 5-10 years on its own?

Hi,

I have had some Boric acid (99.9%) bought a very long time ago... The expiry date was in 2006...

I have used it recently and it is as if it's pure B2O3. Is that even possible??! How could it be?! or is there something I am missing?

The experiment I had done was heating some of this Boric acid along with certain glass modifiers (Na2O and PbO) and the density as well as other optical properties of resulting glass are as if I have used B2O3 in the batch. There hasn't been any weight loss associated with the decomposition of Boric acid either!

thanks in advance...

 

[Dr_Morbius]

When kept at room temperature Boric Acid should last forever. Sometimes though the term "Boric Acid" can be applied to more than one chemical so you should check the label and see what the chemical formula on it says.

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

 

[mubashirmansoor]

its Analytic grade H3BO3...

It has been at room temperature in a poorly sealed plastic container.

 

[Borek]

The experiment I had done was heating some of this Boric acid along with certain glass modifiers (Na2O and PbO) and the density as well as other optical properties of resulting glass are as if I have used B2O3 in the batch. There hasn't been any weight loss associated with the decomposition of Boric acid either!

When heated, boric acid starts to decompose below 200°C, I don't see how it could not lose the water - unless it reacted with Na₂O present. Perhaps properties of the glasses you are referring to have error margins wide enough so that they are not an indicator of what have really happened?

To answer directly your question: no, it won't expire nor change to B₂O₃, it is quite stable.

 

[LudusRex]

I cannot definitively answer whether or not boric acid expires or turns into B2O3 after 5-10 years on its own without conducting a thorough analysis and experiment. However, based on my knowledge of chemical reactions and the properties of boric acid, it is unlikely that it would expire or spontaneously turn into B2O3 on its own.

Boric acid is a stable compound and does not easily decompose or react with other substances at room temperature. Its chemical formula is H3BO3, which means it contains hydrogen, boron, and oxygen atoms. B2O3, on the other hand, is a different compound with a different chemical formula (BO3) and structure. It is unlikely that boric acid would spontaneously convert into B2O3 without any external factors or conditions.

It is possible that the boric acid you have used in your experiment has undergone some changes over time, such as slight impurities or changes in its physical properties. However, it is unlikely that it would turn into B2O3 without any external factors or conditions.

I would recommend conducting further experiments and analysis to determine the exact composition and properties of the boric acid you have used. This will provide a more accurate answer to your question. Additionally, it is always important to check the expiration date of chemicals and to properly store them to ensure their stability and effectiveness.