Question

When the pH of the solution equals the pKa of an indicator, the solution will have an intermediate color. Estimate the pKa of bromocresol green, the indicator that made the transition in the acidic region of the titration.

Answer 1

pKa bromocresol green is ≅4.5

Step-by-step explanation:

The bromocresol green is a chemical indicator used in titrations with equivalence point at pH's between 3 and 5.

Is an indicator that, in acidic region is yellow, and in basicic region is blue. The intermediate color is green (at pH≅ 4.5).

As at the intermediate color of the indicator pKa = pH,

pKa bromocresol green is ≅4.5