Question

При добавлении фенолфталеина в концентрированную азотную кислоту цвет раствора меняется на оранжевый, а не остаётся бесцветным. Объясните это явление.

Answer 1

Фенолфталеин при попадении в щелочную среду меняет окраску раствора на малиновый, а при попадании в кислотную среду остаётся бесцветным

Answer 2

Phenolphthalein and Nitric Acid Reaction

When phenolphthalein is added to concentrated nitric acid, the color of the solution changes to orange instead of remaining colorless. This phenomenon can be explained by the chemical reaction that occurs between phenolphthalein and nitric acid.

Phenolphthalein is a pH indicator that is commonly used in acid-base titrations. It is colorless in acidic solutions and turns pink or magenta in basic solutions. Nitric acid, on the other hand, is a strong acid with a low pH.

The reaction between phenolphthalein and nitric acid can be summarized as follows:

Phenolphthalein + Nitric Acid → Orange-colored product

The exact mechanism of this reaction is not well-documented in the available search results. However, it is likely that the nitric acid causes a chemical change in the structure of phenolphthalein, resulting in the formation of a new compound that exhibits an orange color.

It is important to note that the specific details of this reaction may require further research or consultation with a chemistry expert.