• kieron115@startrek.website
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    4 days ago

    Is lab grade distilled water more guaranteed to be neutral pH? Because I tested some random distilled water from walmart and it was like 5.5. I then went down a rabbit hole and learned that distilled water is so pure that it just sucks up carbon from the air.

    • PrimeMinisterKeyes@leminal.space
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      4 days ago

      Not only the CO2, but also the glassware you put the water in for measuring can very significantly alter the pH. Some scientists I know systematically screened different, presumably clean, containers because of this effect before progressing with their experiments.

      • Dr. Bob@lemmy.ca
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        4 days ago

        We had a distiller in the department. We’d roll over a cart fill a carboy.

    • fullsquare@awful.systems
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      3 days ago

      it will vary, just after distillation (or RO/ion exchange) it should be closer to 7 then it goes down as carbon dioxide gets absorbed. that’s why it’s buffered everywhere where it matters