How should I go about calibrating my pH controller with a 220 ml bottle of solution?

[Jeremy S]

I just bought a 220 ml bottle of 7.01 calibration solution but it has no directions so I’m not sure if I should just stick the probe into the bottle and then keep reusing it or if I should pour a small amount of the solution into a container and then toss it when I’m finished calibrating the controller. Thanks.

 

[happychem]

What do you mean by pH controller? I'm not familiar with the instrument. Presumably it has some kind of pH reading device. I would think that there must be some way of tweaking it.

So at a guess, not knowing what you're working with, I would say that you should pour out a small amount and mix with distilled water to top up. Never contaminate your stock solution by directly inserting the probe. Insert the probe into solution and calibrate your pH reader so that it is reading a pH of 7.0.

But this is all just a guess. I'm assuming that your pH 7.01 solution is a strongly buffered solution that you can add to distilled water to hold it to a pH of 7.0. But I'm really not sure.

Maybe the best thing to do is to try to find some directions on the web. Find the site for the company that made the solution and/or your pH controller. See if you can find the relevant documentation and if not, send them an e-mail and ask for it.

 

[cbster]

When I calibrate my PH controller I just fill the lid and stick it in there and then dump it out when I am done. hope that helps

 

[Jeremy S]

I contacted Milwaukee Instruments and this is what they said:

You can stick to probe directly into the bottle however you must first rinse the probe off in bottle drinking water or RO water.

Never touch the glass bulbe at the end of the probe just wipe the excess rinse water off the outside of the probe body

By the way, I recommend that you replace that bottle every 6 to 9 months with fresh solution.

Thanks for everyone’s replies.