pH0.5～5.0精密试纸的指示剂成分和变色性能

Indicator Composition and Its Change Colour Properties of pH 0.5-5.0 Special Test Paper

目的分析该试纸的指示剂成分及其变色性能,判断其pH分辨能力的大小。方法用色层分析法和分光光度法鉴别其指示剂组成,用色差计法和分光光度法观测其色品、色调、色差和吸收曲线的特性。结果该试纸含有甲基绿、橙黄IV、溴酚蓝和甲酚红几种指示剂。该试纸在pH0.5~5.0区间,当显色反应间隔为0.5时,相邻pH之间的色差较大。结论该试纸能准确区分pH0.5~5.0各0.5区间的pH值,如用采用色差计法或分光光度法则可测得更为精确的pH值。

OBJECTIVE To analyze the indicator components and observe the chromogenic performance of pH 0.5-5.0 precial test paper,so as to determine its resolution of pH value.METHODS Chromatography and spectrophotometry were used to analyze the indicator components of the test paper,while chromatism meter and spectrophotometry were used to determine its chromaticity,hue,chromatism and absorption curve.RESULTS This test paper was composed of indicators of Methyl Green,Orange IV,Bromophenol Blue and Cresol Red.Its chromatism was much obvious at the chromogenic reaction intervals of 0.5 in the section of pH 0.5-5.0.CONCLUSION In pH 0.5-5.0 this test paper can accurately distinguish the p H value at the intervals of 0.5.Chromatism meter or spectrophotometry can be used to determine p H value more precisely.