Ammonium Sulfide (500ml 20%)

Eriochrome Black T (25gr) Sodium 1-[1-Hydroxynaphthylazo]-6-nitro-2-naphthol-4-sulfonate, Sodium 4-[2-(1-hydroxynaphthalen-2-yl)hydrazin-1-ylidene]-7-nitro-3-oxo-3,4-dihydronaphthalene-1-sulfonate, Sodium 4-[2-(1-hydroxynaphthalen-2-yl)hydrazin-1-ylidene]-7-nitro-3-oxonaphthalene-1-sulfonate; Solochrome Black T; ET-00; Erio T C₂₀H₁₂N₃O₇SNa 461.381 g/mol Cas Number: 1787-61-7 https://en.wikipedia.org/wiki/Eriochrome_Black_T

Bromothymol Blue (5gr)