Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET2012Chemistryd and f Block ElementsActual

Which of the statements is not true?

Options

  1. AOn passing H ₂ ~S through acidified K ₂ Cr ₂ O ₇ solution, a milky colour is observed
  2. BNa ₂ Cr ₂ O ₇ is preferred over K ₂ Cr ₂ O ₇ in volumetric analysis
  3. CK ₂ Cr ₂ O ₇ solution in acidic medium is orange
  4. DK ₂ Cr ₂ O ₇ solution becomes yellow on increasing the pH beyond 7

Correct answer

B. Na ₂ Cr ₂ O ₇ is preferred over K ₂ Cr ₂ O ₇ in volumetric analysis

Step-by-step solution

Being hygroscopic, sodium dichromate, Na ₂ Cr ₂ O ₇ cannot be used in volumetric analysis. All other given statements are true.

Practice d and f Block Elements on Quantrex Academy →

More from d and f Block Elements

Although +3 oxidation state is most common in lanthanoids, cerium still shows +4 oxidation state because : 2026The lanthanide ion having four unpaired electrons is (Given : Atomic numbers of Ce =58 , Nd =60 , Tb =65 and Ho =67 ) 2026The green paramagnetic species formed by heating KMn O₄ at 513 K is 2026The calculated 'spin-only' magnetic moment of Ti ²⁺ (3d^2) is : 2026Match List I with List II : List I (Transition metal/compound/complex) List II (Catalytic Role) A. V ₂ O ₅ I. Preparation of ammonia from N ₂/ H ₂ mixture B. Fe II. Polymerisation 2026Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R . Assertion A : Generally, 3d transition metals have high melting points. Reas 2026Given below are two statements : Statement I : Ferromagnetism is considered as an extreme form of paramagnetism. Statement II : The number of unpaired electrons in a Cr ²⁺ ion ( Z 2025Which of the following set of ions act as oxidising agents? 2024 Full d and f Block Elements list All NEET PYQs