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Tashiro's indicator

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Tashiro's indicator is a pH indicator (pH value: 4.4–6.2), mixed indicator composed of a solution of methylene blue (0.1%) and methyl red (0.03%) in ethanol[1][2][3] or in methanol.[4]

Tashiro's indicator (pH indicator)
below pH 4.4 above pH 6.2
4.4 6.2

Used e.g. for the titration of ammonia in Kjeldahl analysis.

Colours

The function of the methylene blue is thus to change the red-yellow shift of methyl red to a more distinct violet-green shift.

See also

References

  1. ^ Willmes, Arnold (2007). Taschenbuch Chemische Substanzen. Frankfurt am Main. ISBN 978-3817116621. Retrieved 30 March 2016.{{cite book}}: CS1 maint: location missing publisher (link)
  2. ^ Tashiro’s indicator solution in ethanol
  3. ^ SDS
  4. ^ Tashiro’s indicator solution in methanol