CAS Registry Number

CAS 23647-14-5 — 2-(4-Sulfophenylazo)1,8-dihydroxy-3,6-naphthalenedisulfonic acid trisodium salt (SPADNS)

CAS 23647-14-5 C16H9N2Na3O11S3 MW 570.41

2-(4-Sulfophenylazo)1,8-dihydroxy-3,6-naphthalenedisulfonic acid trisodium salt (SPADNS) is a synthetic azo dye widely used as a pH indicator and complexometric titrant in analytical chemistry, particularly for calcium and magnesium determinations. It appears as a dark red-orange powder, soluble in water, with a sharp color transition from red to blue in alkaline conditions. CAS 23647-14-5, molecular formula C16H9N2Na3O11S3, molecular weight 570.41 g/mol. Stored at ambient temperatures, non-hazardous under normal handling. Molekula supplies SPADNS from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

View product details

Molekula products for CAS 23647-14-5

2-(4-Sulfophenylazo)1,8-dihydroxy-3,6-naphthalenedisulfonic acid trisodium salt (SPADNS)

SKU 20091190

Made to order

Molekula has supplied fine chemicals and biochemicals since 2000 from ISO 9001:2015 and ISO 14001:2015 certified facilities. Every dispatched batch is logged with a batch number and matched to a Certificate of Analysis, and Safety Data Sheets are available in five languages.