Chemical Entity Data Page

Acid-base indicator (AS/A2 generic)
pH indicator (generic)
  Belongs to a sub-set of generics specific to the British A-Level exam system.

A (Brønsted) acid-base indicator is an organic acid (with some water solubility) which has acid and base forms with different colours.

At least one of the forms must have a very intense colour so that only a very small amount of indicator is required. This condition is necessary so the indicator does not interfere with the titration.
Wikipedia Page:

Acid-base indicator (AS/A2 generic)
is defined with respect to the entities below:
The entities below are defined with respect to:
Acid-base indicator (AS/A2 generic)
Alizarin yellow GG

Bromothymol blue


Methyl orange

Methyl red

Phenol red


Thymol blue, sodium salt

© Mark R. Leach 1999 –

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