• British Pharmacopoeia Volume V
  • Appendices
  • Appendix I A. General Reagents

Mordant Black 11

Mordant Black 11 CI 14645; eriochrome black T; solochrome black; C20H12N3NaO7S = 461.4 (1787-61-7)

General reagent grade of commerce.

A brownish black powder.

Produces a red colour with calcium, magnesium, zinc and certain other metals in alkaline solutions. When metal ions are absent, for example in the presence of an excess of disodium edetate, the solution is blue.

Store in an airtight container protected from light.