Safety Reference
Danger
H301Toxic if swallowed
H331Toxic if inhaled
H400Very toxic to aquatic life
H410
Restricted or banned substances
Substances on this list are banned or restricted under the named regulation. This page is a compliance reference — verify your obligations under applicable law.
CAS 520-10-5
2-Nitro-3-aminothiophene
research compound
Arsenazo I is a metallochromic dye reagent used primarily for the detection of calcium ions. It functions as a sensitive indicator in analytical chemistry for metal ion determination.
Content scope: Information here supports chemical identification and industrial supply, research, and manufacturing contexts. It is not a therapeutic claim, medical advice, or drug-use instructions.
The international HS code for Arsenazo I (CAS 520-10-5) is 2931.90.
2931.90
2931 90 00
Classification per the EU customs inventory ECICS (2026-07 snapshot, HS 2022). National tariff lines and product form can affect the final classification.
3-[(2-arsonophenyl)diazenyl]-4,5-dihydroxynaphthalene-2,7-disulfonic acid
NJZWLEZSGOTSHR-UHFFFAOYSA-N
C1=CC=C(C(=C1)N=NC2=C(C3=C(C=C(C=C3C=C2S(=O)(=O)O)S(=O)(=O)O)O)O)[As](=O)(O)O