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NTA Abhyas JEE Main2020ChemistryRedox ReactionsPractice

Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthalein indicator only in presence of:

Options

  1. Atrans-glycerol
  2. Bcatechol
  3. Ccis-glycerol
  4. Dboth B and C

Correct answer

D. both B and C

Step-by-step solution

It forms a stable cyclic complex with polyhydroxy compounds like cis-glycerol, catechol, etc. This helps in the release of H + a s H 3 O + therefore, boric acid acts as a strong acid and hence can be titrated with sodium hydroxide using phenolphthalein.

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