Abstract:

The color reaction of Ca²⁺ with Kalces,many factors of influence on the sensitivity and stability and the optimium operational conditions have been studied.The experimental results reveal that in the presence of HAc-NaAc buffersolution medium(pH5.2),Ca²⁺ can react with Kalces to form a 1:1 blue complex.The molar absorptivity is 1.33×10⁴L/(mol⋅cm)at 620nm.Under this wavelength and optimum operational conditions ,when the concentration range of calciumcontent is 0~1.6mg/L,Beer's law is obeyed.On the basis of testing 10 kinds of common coexistent interferingions,this method can be applied to the determination of Ca²⁺ in 6 kinds of water samples.The recovery ratio is 95.6% to 103%.It is very satisfactory.

Key words: Kalces, spectrophotometric, determination of calcium

摘要：

研究了钙指示剂(Kalces)与钙作用的显色体系,试验了影响该显色体系的灵敏度和稳定性的各项因素,确定了最佳操作条件.试验表明,在pH为5.2的乙酸-乙酸钠缓冲介质中,钙指示剂与钙生成蓝色1:1的配合物,λmax=620nm,体系表观摩尔吸光系数ε=1.33×104L/(mol⋅cm),在此波长及最佳操作条件下,钙含量在0~1.6mg/L质量浓度范围内符合比尔定律.在试验了19种常见共存离子干扰的基础上对6种水样的钙度进行测定,回收率在96.5%~103%之间,结果满意.

关键词: 钙指示剂, 分光光度法, 钙的测定

CLC Number: 

• X832