Given the following, which pH indicator should the scientist use?

A scientist wants to test how much of an acid can be added to a solution scientist 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 5.0.

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1 Answer
Mar 30, 2017

You will need an indicator that has a colour change very close to the desired pH. Methyl red or bromcresol green will do for this one.

Explanation:

The indicators mentioned above show colour changes in the range of pH 5.0. If you do not pick an indicator that changes colour at a value close to the desired endpoint (5.0 in this case), you will not be able to determine when the solution passes through this pH value.