Hanna ph checker how to dilute a sample

[nobody]

Hello.
I have been getting a high warning on the ph checker. Its says to dilute the sample and retest but how do you dilute a new sample.?
Thanks

 

[Jay Hemdal Verified Community Expert]

I think that is a generic instruction for all of their Hanna checkers. I do not know of any way to dilute a sample for pH and then be able to back calculate to get a reading. For example, is a copper reading was off the scale, diluting the sample 50% with RODI water and retesting would bring it back into range, I would then just multiple the results by two.
In this case, I don’t see how you could do that. I would look for a second way to double check the pH.
Jay

 

[Dcloser12]

Add 10ml, don't go via the line on the vial and make sure you drip 5x very slowly. If you squeeze the bottle to force the drips it adds a bit more than it should. Retest with this method. Any time I get a wacky high reading I retest 2x with this method and they are normally 8.4 spot on.

 

[Randy Holmes-Farley Verified Community Expert]

I know this is old but...diluting is not a suitable thing to do before measuring pH.

Interestingly, if you add totally pure fresh water at pH 7.0 to seawater at pH 8.2, the final pH will be above 8.2!

The wonders of chemistry!