Solochrome Dark Blue

Solochrome dark blue or calcon ( C.1.15705). This is sometimes referred to as eriochrome blue black RC it is in fact sodium l-(2-hydroxy-l-naphthylazo)-2-naphthol-4-sulphonate. The dyestuff has two ionisable phenolic hydrogen atoms the protons ionise stepwise with pK values of 7.4 and 13.5 respectively. An important application of the indicator is in the complexometric titration of calcium in the presence of magnesium this must be carried out at a pH of about 12.3 (obtained, for example, with a diethylamine buffer 5 mL for every 100 mL of solution) in order to avoid the interference of magnesium. Under these conditions magnesium is precipitated quantitatively as the hydroxide. The colour change is from pink to pure blue. 

Solder analysis of by EDTA, (ti) 337 Solochrome black 317, 692 Solochrome (Eriochrome) cyanine R 678 Solochrome dark blue 318 Solubility product 24 calculations involving, 25 importance of, 26 principal limitations of, 24 Solution of sample 110 Solvents amphiprotic, 282 aprotic, 282 ionising, 18 non-protonic, 18 protogenic, 18, 282 protophilic, 282... 

Solochrome black T, solochrome dark blue at 520 nm [109] W(VI)-catechol violet at 650 nm [110] o-Hydroxy-quinolphthalein at 525 nm [111]... 

Some of the metal ion indicators used for calcium and magnesium are discussed below Solochrome dark blue or calcon... 

Dihydroxy-1,I -azonaphthalene (Solochrome Dark Blue) 20 15 2 2 78SMa... 

Hydroxy-4-[ 2 hydroxy l naphthalenyl)azo]-l-naphthalenesulfonic acid, 9CI. 2,1-Dihydroxy-1,1 -azonaphthalene-4-sulfonic acid. Calcon. Palatine chrome black 6BN. Solochrome dark blue B. Diamond blue black EB. C.L Mordant blue 17. C.I. 15705 [2538-79-6]... 

Solbrol A, in H-OOl 13 Solochromate fast violet B, see H-00556 Solochrome azurine BS, S-00016 Solochrome black AS (free acid), see H-00224 Solochrome black 6BN, S-00017 Solochrome black PV, S-00018 Solochrome black RN, see S-00019 Solochrome black WDFA. see C-00278 Solochrome brilliant blue, see C-00277 Solochrome cyanine R, ee E-00013 Solochrome dark blue B, see E-OOOlO Solochrome fast blue B, in A-00225 Solochrome fast grey RA, S-00019 Solochrome fast grey RAS, see E-00014 Solochrome fast red, S-00020 Solochrome green V, see C-00132 Solochrome orange RS, see C-00289 Solochrome red B, S-00021... 

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