摘要
在混合碱溶液的分析测定中，用混合指示剂代替惯用的酚酞－－甲基橙双指示剂，由于多种颜色的交叉迭加，在滴定过程中外观变化色相丰富，色差加大，色段切细，使第一计量点的判断容易准确把握，第二计量点变色特征依然鲜明易断。随机抽调学生对该方法的操作统计数据表明Ｎａ２ＣＯ３－ＮａＨＣＯ３混合碱测定的误差得以明显的改善。
In analysis and determination of mixed alkali,the habitually practised double indiator, phenolphalein-methyl orange,was replaced by the mixed indicator,because of crossing and occumulation of many kinds of colours,the tincture was rich in outward appearance,the chromatism increased,the vitta was fine,in the process of titration,the determination of the first measure piont was easy, the character of changing colour in the second measure point was still clear and the judement was easy,so that the error of determination using mixed soda Na2Co3-NaHco3,obtained a clear improvement,which was showed by the result of determination of students selected at random.
出处
《宁夏农学院学报》
1996年第1期46-51,共6页
Journal of Ningxia Agricultural College
关键词
混合指示剂
混合碱
测定
变色点
mixed indicator
determination using mixed alkali
the point of changing colour
significance
