What is a good property of an indicator?

Acid base indicators are weak and acids and bases, which are used to signify the end point of neutralization reaction. The type of indicator used for a neutralization reaction depends on the strength of the acid and the base, that are involved in the reaction. A good acid base indicator must have a good pH range and it must be able to produce specific and identifiable color in specific acid base medium.

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Two good properties of an indicator are as follows-

1) It should be specific- It means that the changes, which are measured by the indicator should be expressed in precise terms so that appropriate assessment could be made.

2) It should be time bound- This means that the measurable changes should arrive withing a particular time limit.

Example of indicator- Litmus is an acid base indicator that turns acidic solutions red and basic solutions into blue color.