Why is the PHS-3S compact pH meter inaccurate?
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After being calibrated according to the instructions, the PHS-3S compact pH meter enters standby mode. When measuring calibration solutions, it generally yields the correct pH value. However, when measuring distilled water, the pH value is around 5.5, while a test strip gives a value of 7.0. Of course, test strips cannot be wrong; what’s unclear is why the meter gives an accurate reading when measuring calibration solutions but not when measuring other liquids I hope those who have used this machine can give some advice.
The regular electrodes used with pH meters cannot be used to measure the pH value of distilled water; there are specialized electrodes designed for pure water, and you just need to purchase one of such electrodes.
Thank you! Is it possible to measure oil quality then? Are there also specialized measuring electrodes for that?
Measuring pH value determines the concentration of hydrogen ions in a solution. Oil is a non-aqueous solution that contains no hydrogen ions, so it cannot be measured using a pH meter.
There are specialized instruments for measuring oils. You can take a look at http://sjzjwdyq.cn.alibaba.com/page/offerlist.htm?tradenumFilter=false&priceFilter=false&mixFilter=false&privateFilter=false&groupFilter=false&sortType=tradenumdown&pageNum=22#search-bar