NaOH滴定H3PO4(pKa1~pKa3分别为2.12,7.20,12.36)至产物为Na2HPO4,应选用的指示剂是()A、甲基橙B、甲基红C、酚酞D、百里酚酞

NaOH滴定H3PO4(pKa1~pKa3分别为2.12,7.20,12.36)至产物为Na2HPO4,应选用的指示剂是()

  • A、甲基橙
  • B、甲基红
  • C、酚酞
  • D、百里酚酞

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