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JEE Main20265 April 2026Morning ShiftChemistryRedox ReactionsActual

Given below are two statements: Statement I: Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis. Statement II: Phenolphthalein is a weak base, therefore it dissociates in acidic medium. In the light of the above statements, choose the correct answer from the options given below

Options

  1. ABoth Statement I and Statement II are true
  2. BBoth Statement I and Statement II are false
  3. CStatement I is true but Statement II is false
  4. DStatement I is false but Statement II is true

Correct answer

B. Both Statement I and Statement II are false

Step-by-step solution

Statement I is false because sodium dichromate is deliquescent (absorbs moisture from the atmosphere) and cannot be weighed accurately, so it is not used as a primary standard. Potassium dichromate, however, is a primary standard. Statement II is false because phenolphthalein is a weak organic acid, not a weak base. It remains largely undissociated in an acidic medium (colorless) and dissociates in a basic medium to give a pink color. Therefore, both Statement I and Statement II are false. Answer: Both Statement I

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