称取K2Cr2O70.2784g溶于水,用Na2S2O3溶液滴定至终点,消耗26.10ml,计算Na2S2O3溶液的当量浓度.

问题描述:

称取K2Cr2O70.2784g溶于水,用Na2S2O3溶液滴定至终点,消耗26.10ml,计算Na2S2O3溶液的当量浓度.

0.2784gK2Cr2O7的克当量数=6*0.2784/294.18=0.0056781
Na2S2O3溶液的当量浓度=0.0056781/0.02610=0.2176N