Why do acid and alkaline solutions get colorful when exposed to indicators?
In: Chemistry
It is the indicator molecule that changes colour based on pH (presence and concentration of acids and bases) of the solution. Indicators are complex organic molecules with a finely balanced system of different bonds. This system is balanced in such a way that a molecule absorbs a specific wavelength of light and so appears in a specific colour. When pH of solution changes, because some acid or base is added, indicator molecule may also lose or receive a hydrogen atom. This changes the balance of the molecule, making it absorb a different wavelength, and appear in different colour.
The INDICATORS get colorful when exposed to alkaline or acid solutions. The indicators are chemicals that are designed to change color (interact with light differently) when they react with an acid or an alkaline.
If you look at [phenolphthalein](https://en.wikipedia.org/wiki/Phenolphthalein), you can see how its molecule changes with the formation of an acidic (-COOH) section or a basic ( -OH) section, and the new configuration of the molecule absorbs various frequencies (colors) of light differently, thus changing colors.
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