Question

A scientist wants to test how much of an acid can be added to a solution

before the pH of the solution changes to below a certain point. The starting
pH of the solution is 6.0, and the scientist wants to know when the pH of the
solution changes to below 4.0.
Which pH indicator should the scientist use?
A. Methyl violet, which changes from violet to yellow around a pH of
2.0
B. Methyl yellow, which changes from yellow to red around a pH of
4.0
C. Cresol red, which changes from yellow to purple around a pH of
7.2
O
D. Thymolphthalein, which changes from colorless to blue around a
pH of 9.3

Answer 1

b.

Step-by-step explanation:

Answer 2

B. Methyl yellow, which changes from yellow to red around a pH of

4.0

Step-by-step explanation:

A pH indicator is a technique by which the pH of a solution can be known. The scenario in the question describes that the scientist wants to determine a pH after it gets converted from 6 to below 4. For this recognition, the scientist should use a methyl yellow indicator which will change from yellow to red once a pH around 4 is achieved.