Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETChemistryd and f Block Elements

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): V₂O₄ dissolves in acids to give VO²⁺ salts, whereas V₂O₅ dissolves in acids to give VO₂^+ salts. Reason (R): Vanadium retains its +4 oxidation state in the VO²⁺ ion and its +5 oxidation state in the VO₂^+ ion. In the light of the above statements, choose the most appropriate answer from the options

Options

  1. ABoth Assertion (A) and Reason (R) are correct and Reason (R) is the correct explanation of Assertion (A).
  2. BBoth Assertion (A) and Reason (R) are correct but Reason (R) is not the correct explanation of Assertion (A).
  3. CAssertion (A) is correct but Reason (R) is not correct.
  4. DAssertion (A) is not correct but Reason (R) is correct.

Correct answer

A. Both Assertion (A) and Reason (R) are correct and Reason (R) is the correct explanation of Assertion (A).

Step-by-step solution

Assertion (A) is correct. According to NCERT, V₂O₄ dissolves in acids to give VO²⁺ (vanadyl) salts. On the other hand, V₂O₅ is an amphoteric oxide that dissolves in acids to give VO₂^+ (dioxovanadium) salts. Reason (R) is also correct and explains the Assertion. The dissolution of these oxides in acids is a non-redox process. In V₂O₄ , the oxidation state of vanadium is +4 , which is retained in the VO²⁺ ion (let the oxidation state be x , then x - 2 = +2 x = +4 ). In V₂O₅ , the oxidation state of vanadium is +5 ,

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