Spectrophotometric determination of silver with 1-pyridine-3-(4-phenylazophenyl)-triazene

The color reaction of 1-pyridine-3-(4-phenylazophenyl)-triazene(PYPAPT) with silver was studied.In the presence of nonionic surfactant TritonX-100 and in the medium of NaOH,silver can react with 1-pyridine-3-[4-phenylazophenyl]-triazene to form a reddish-brown complex with ratio of 1∶2.The maximum negative absorption of the complex is at 530 nm,at which apparent molar absorptivity of the complex is 4.23×104 L·mol-1·cm-1.Beer's law is obeyed in the range of 0-2.50 mg/L for silver.The proposed method has been applied to the determination of silver in lead ore samples.The results are consistent with the values obtained by atomic absorption spectrometry.