I am an undergraduate student majoring in physics. I am looking for the best method to accurately measure the volume of strong acids like hydrobromic $(w(\ce{HBr(aq)}) = 48\,\%)$ and hydroiodic $(w(\ce{HI(aq)}) = 57\,\%)$ acids. I need milliliter volumes, and since I'm going to pour or dispense a specific volume of acid in a vial, I mean "to deliver". The only measuring device I could think of is a mechanical pipette, but I am afraid the acids or their corrosive vapors could damage the pipette's mechanism.

I don't have any friends or colleagues majored in chemistry, so I am having a hard time trying to decide which pipette to buy. I really have no clues on how actual chemists who use strong acids accurately measure them, so I'll be pleased with any kind of help.

  • 3
    $\begingroup$ Concentrated acids are seldom measured precisely, as their concentration is not precise either. $\endgroup$
    – Poutnik
    Commented Sep 18, 2022 at 8:06
  • $\begingroup$ I think there are Hamilton syringes with glass/PTFE inserts/fittings which could resist these strong acids. But it's probably preferable to just weigh the acids instead if you can. $\endgroup$ Commented Sep 18, 2022 at 11:00
  • $\begingroup$ Maybe your advisor has friends who are chemists. It would be nice to have access to a chemist for considerations of safety and hazardous waste treatment. $\endgroup$
    – Karsten
    Commented Sep 18, 2022 at 11:52
  • 2
    $\begingroup$ Metallic pieces should be avoided, because they react with acids. But glass pipettes and rubber bulbs are resistant to strong acids like $\ce{HCl, HBr, HI}$ in solution or in a gaseous state. $\endgroup$
    – Maurice
    Commented Sep 18, 2022 at 14:08
  • $\begingroup$ PE/PP Hamilton syringe inserts should work too, unless it is for perchloric acid. $\endgroup$
    – Poutnik
    Commented Sep 18, 2022 at 14:19


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