Ascornic acid or sodium thiosulfate can beused as titrant in the determination of 3,5-di-hydroxybenzoic acid. At the end point, thelight point on the oscillograph screen movesupward rapidly.

• 本文报道了利用溴酸盐法零电流示波电位滴定法直接和间接滴定3，5-二羟基苯甲酸的含量。操作简便，终点指示明显，测定结果良好。