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Old 15-07-2006, 01:48 AM   #3
BarraCuda™
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Why calibrate?

The accuracy of pH measurement depends largely on the quality of the electrode. However manufacturers cannot make pH electrodes that will give a absolute exact voltage at a certain pH value, hence there is a need to let your pH meter "know" the electrode.


What type of calibration/buffer solution?

pH buffer commonly come with pH4.00, pH7.00 and pH10.00. Any buffer solutions with reputable brands will do as they are traceable to national standards.

If you are measuring acidic liquid, you should use pH4 and pH7 buffers. If you are measuring alkaline liquid, you should use pH7 and pH14.


Why the difference?

By letting your pH meter "know" what is the exact value at least 2 reference pH, the pH meter can better calculate the pH slope between these 2 values. That explains the need for different calibration solutions.
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