Qualitative methods can be determined by pH indicator and pH test paper, and quantitative pH determination requires pH meter.
Hydrogen ion concentration index, commonly known as "pH", was put forward by Danish biochemist Soren Peter Laurits Sorensen in 1909. P comes from German Potenz, which means concentration and intensity, and H (hydrogen ion) stands for hydrogen ion.
Extended data:
There are many ways to determine the pH value of a solution:
1. Use the pH indicator. When pH indicator is added to the solution to be tested, different indicators will change color according to different pH values, and the pH range can be determined by studying the indicators. When titrating, an accurate pH standard can be made.
2. use pH test paper. There are many kinds of PH test paper and precision test paper. Dip a little solution to be tested on the test paper with a glass rod, and then get the pH value of the solution according to the color change of the test paper and the standard color card. The pH test paper cannot show the pH value of the oil, because the pH test paper measures the pH value of the solution to be tested with hydrogen ions, and the oil does not contain hydrogen ions, so the pH test paper cannot show the pH value of the oil.
3. Use an acidity meter. Acidimeter is an instrument for measuring the pH value of solution. It measures the pH value of the solution through a pH selective electrode (such as a glass electrode). The acidity meter can be accurate to two decimal places.
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