Hi can i please have some help thanks ?
1 Answer
(a) acidic solutions
Indicators are compounds that have different colours depending on the pH of the solution.
Many indicators are weak acids in which the acid and base forms have different colours.
For example, we could write the equilibrium for phenolphthalein as
The cyanidins have three forms: acid, neutral, and base.
We could write the equations for their equilibria as
The points to note are:
- The neutral form has no charge
- The acidic form has one more proton, i.e. a positive charge
- The basic structure has one less proton, i.e. a negative charge
Thus, the equilibria are