PH test paper is used to test the pH of the solution of the "ruler", also called litmus test paper. There are three indicators on the PH test paper, methyl red, bromocresol green and thymol blue, and they will change color according to a certain rule in the solution of different PH values.
PH test paper is used to test the pH of the solution of the "ruler", also called litmus test paper. There are three indicators on the PH test paper, methyl red, bromocresol green and thymol blue, and they will change color according to a certain rule in the solution of different PH values. The PH test paper is widely used. When testing the pH of the solution, a clean and dry glass rod is used to dip the tested liquid into the middle of the test paper, observe the color after the change and stability, and compare with the standard colorimetric card to judge the nature of the solution. When testing the pH of the gas, first wet the test paper with distilled water, stick it to one end of the glass rod, and then send it to the mouth of the container containing the gas to be measured, observe the change in color, and judge the nature of the gas.
When using, tear off a strip, put it in the surface dish, dip a dry glass rod into a drop of the solution to be tested, drop it in the middle of the test paper, and then compare the color change of the test paper with the standard colorimetric card to know the acid-base degree of the solution, which is very convenient. pH test paper can be divided into 0.2 grade, 0.1 grade, 0.01 grade or higher accuracy according to the measurement accuracy.
Product Description
1, take the test strip immersed in measurable solution, half a second later take out and compare with the standard color plate, obtain the PH value:
2, the test paper is not suitable for very weak buffer solution and concentration of less than 0.01% acid and base solution;
3. The test paper should be stored in a dry place away from light.
How Use:
1. Check the pH of the solution: tear off a strip of test paper, drop the solution with a plastic head dropper, change color for half a second and compare with the color card on the package; Or take a small amount of solution, wet the liquid directly with the test paper, and compare it with the color card on the package for half a second; You can also take a small piece of test paper on the surface dish or glass sheet, dip a clean and dry glass rod into the middle of the test paper, observe the color after the change and stability, and compare with the standard colorimetric card to judge the nature of the solution.
2. Test the acid and alkalinity of the gas: first wet the test paper with distilled water, stick it to one end of the glass rod, and then send it to the mouth of the container containing the gas to be measured, observe the change in color, and judge the nature of the gas. (The test paper should not touch the wall)
Look Out
1. The test paper should not be directly inserted into the solution.
2. The paper can not measure the pH of concentrated sulfuric acid.
3. Do not touch the test tube mouth, bottle mouth, catheter mouth, etc.
4. When determining the pH of the solution, the test paper should not be moistened with distilled water in advance, because this will lead to inaccurate measurement. The correct method is to drop a glass rod dipped in the solution to be measured in the middle of the test paper, wait for the test paper to change color, and then compare with the standard colorimetric card to determine the pH of the solution.
5. After taking out the test paper, the container containing the test paper should be tightly covered to avoid being contaminated by some gases in the laboratory
6. It must be used at room temperature, otherwise it will lead to inaccurate results.
