Aladdin indicator is a kind of chemical reagent.

Under certain medium conditions, its color can change, turbidity or precipitation can be produced, and there are fluorescence phenomena.?It is commonly used to test the acidity and alkalinity of solutions, to indicate the titration end point in titration analysis, and to test harmful substances in environmental detection.?Aladdin indicators are generally divided into acid-base indicators, redox indicators, metal indicators, adsorption indicators, etc.

Indicator a reagent used to indicate the end point of titration.?In various titration processes, with the addition of titrant, the concentration of the substance to be titrated and the titrant are constantly changing. Near the equivalence point, the ion concentration will change greatly. The reagent that can display the change of ion concentration (such as changing the color of solution, generating precipitation, etc.) is called indicator.?If the titrant or the substance to be titrated is colored, they themselves have the function of indicator, such as potassium permanganate.

The history of indicator development dates back to the 17th century.?This substance has been used by many practical chemists in that ancient era. During the experiment, they collect and sort the plant juice (i.e. indicator) and stain it on a small piece of paper, and then drop a drop of the solution they studied on this test paper to judge some properties of the chemical reaction they studied.?According to the existing records, Boyle was the first scientist to use the juice of various natural plants as indicators. Some of these indicators were prepared into solutions or test papers.