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有一磷酸盐溶液,可能由Na3PO4,Na2HPO4和NaH2PO4或其中二者的混合物组成。今以百里酚酞为指示剂,用盐酸标准滴定溶液滴定至终点时,消耗V1ml,再加入甲基红指示剂,继续用盐酸标准滴定溶液滴定至终点时,又消耗V2ml。当V2>V1,V1>0时,溶液的组成为:()。

  • A、Na2HPO4和NaH2PO4;
  • B、Na3PO4;
  • C、Na2HPO4;
  • D、Na3PO4和Na2HPO4;
  • E、Na3PO4和Na2HPO4

参考答案

更多 “有一磷酸盐溶液,可能由Na3PO4,Na2HPO4和NaH2PO4或其中二者的混合物组成。今以百里酚酞为指示剂,用盐酸标准滴定溶液滴定至终点时,消耗V1ml,再加入甲基红指示剂,继续用盐酸标准滴定溶液滴定至终点时,又消耗V2ml。当V2V1,V10时,溶液的组成为:()。A、Na2HPO4和NaH2PO4;B、Na3PO4;C、Na2HPO4;D、Na3PO4和Na2HPO4;E、Na3PO4和Na2HPO4” 相关考题
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