用盐酸溶液滴定Na2CO3溶液的第一、二个化学计量点可分别用()为指示剂。A、甲基红和甲基橙B、酚酞和甲基橙C、甲基橙和酚酞D、酚酞和甲基红E、溴甲酚绿-甲基红

用盐酸溶液滴定Na2CO3溶液的第一、二个化学计量点可分别用()为指示剂。

  • A、甲基红和甲基橙
  • B、酚酞和甲基橙
  • C、甲基橙和酚酞
  • D、酚酞和甲基红
  • E、溴甲酚绿-甲基红

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