Single point calibration of ph meter
Any kind of pH meter can only measure the pH of a sample after it has been calibrated with a pH standard solution. For samples whose measurement accuracy is below 0.1 pH, the instrument can be adjusted slightly, generally using a buffer of pH 6.86 or pH 7.00. The accuracy of some instruments is only 0.2pH or 0.1pH, so the instrument is only equipped with a positioning adjustment knob. The actual operation steps are as follows:
(1) Measure the temperature of the specification buffer, look up the table to determine the pHs value at this temperature, and adjust the temperature compensation knob to this temperature.
(2) The electrode was developed with pure water and spin-dried.
(3) Shake the electrode to soak the buffer solution, and then let it stand. After the reading is stable, adjust the positioning knob so that the instrument displays the pH value of the solution of this specification.
(4) Take out the electrode, wash and spin dry.
(5) Measure the temperature of the sample, and adjust the temperature compensation knob of the pH meter to the temperature value.
