摘要
研究了新显色剂二溴对甲基偶氮溴羧与钡显色反应的条件。在磷酸介质中,试剂与钡形成2:1的络合物,最大吸收波长为610nm,摩尔吸光系数为2.13×10~4L·mol^(-1)·cm^(-1),钡量在0～20μg/25ml范围内符合比耳定律。两倍的锶和五倍的钛不干扰,钙的允许量较大,方法用于直接测定钛酸钡烧结物中微量钡,结果满意。
A study on the color reaction of 2-( 4-bromo-2-carboxyphenylazo )-7-( 2, 4-dibromo-4-methylphenylazo)-l,8-dihydroxynaphthalene-3. 6-disulfonic acid (abbreviated as BCA-DBM) with barium is reported in this paper. It is found that a 2 ' 1 complex between BCA-DBM and Ba^(2+) is formed in a H_3PO_4 medium, with an apparent molar absorptivity of 2.13×10~4L ·mol^(-1) ·cm^(-1) at its absorption maxima of 610nm; and that Beer's law holds in the concentration range of 0 to 20μg/25ml of barium. Two fold amounts of strontium, 5-fold amounts of titanium and 30-fold amounts of calcium are tolerable. The proposed method has been applied to the determination of trace amounts of uncombined barium in sintered material of barium titanate with satisfactory results.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
1999年第3期101-102,共2页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
二溴对甲基
偶氮溴羧
吸光光度法
钡
显色反应
2-(4-bromo-2-carboxyphenylazo )-7-(2,4-dibromo-4-methy phenylazo )-l, 8-dihydroxy-naphthalene-3,6-disulfonic acid, Absorptiophotometry, Barium, Barium titanate
