Indicators

Indicators
Indicators, the colours of which change over approximately the same range of pH, may be substituted for one another but in the event of doubt or dispute as to the equivalence of indicators for a particular purpose, the indicator specified in the text is alone authoritative.
The quantity of an indicator solution appropriate for use in acid-base titrations described in assays or tests is 0.1 ml unless otherwise stated in the text.
Any solvent required in an assay or test in which an indicator is specified is previously neutralised to the indicator, unless a blank test is prescribed.