pH meter is an important tool in chemistry mostly used in pharmaceuticals to determine the acidity or alkalinity of different solutions. It consists of a pH probe that passes electrical signals to the pH meter and displays the pH value of the solution. For accurate measurements, however, pH meters requires proper calibration by dipping it into test solution of known pH and adjusting the meter accordingly. The test solution of known values called buffers. Learn how to calibrate a pH in three ways.
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