View Single Post
Unread 05/19/2017, 07:24 AM   #5
Dan_P
Registered Member
 
Join Date: Aug 2014
Posts: 1,432
If you have the energy to "figure out" the testing conflict, run the alkalinity titration for each kit with a pH in the test solution. The pH should be about 4.3 at the neutralization point, where the color has just completely changed. This approach will eliminate any error caused by confusing color changes. If the pH is not calibrated, you can still use the pH readings. Regardless of the actual pH, determine whether the endpoint occured at roughly same pH (it will if both kits are working, or broken in exactly the same way which is unlikely).

If the titration results still vary widely, you can conclude the the titrant strength is off. Determining which titrant is the corect strength would require having access to a standard with a known alkalinity.

The calcium titration differences are close enough to suggest that improving technique will get them closer.


Dan_P is offline   Reply With Quote