Ammonium salt of aurin tricarboxylic acid aluminon

AMMONIUM SALT OF AURIN TRICARBOXYLIC ACID ( ALUMINON ) 

Formaldehyde condenses with salicylic acid in the presence of nitrite-containing sulphuric acid to give aurin tricarboxylic acid this is converted by ammonia solution into the ammonium salt, which is employed as a reagent for aluminium ( aluminon )  

The substance is employed under the name of Magneson II as a test for magnesium. 

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Aluminum in solution of its salts is detected by the reaction (1) with ammonium salt of aurin tricarboxylic acid ( aluminon ), which yields a red precipitate persisting in NH4OH solution, (2) with alizarin red S. which yields a bright red precipitate persisting in acetic acid solution. 

Aluminon (qualitative test for aluminum). The reagent consists of 0.1% solution of the ammonium salt of aurin tricarboxylic acid. A bright red precipitate, persisting in alkaline solution, indicates aluminum. 

Aluminon (a solution of the ammonium salt of aurine tricarboxylic acid) Quinalizarin, alizarin-S, alizarin Chromium (III), Cr3 Ammonia solution... 

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