CBSE 2022 · Region 4 · Set 1 · Q6 · 3 marks
(i)Which ion amongst the following is colourless and why? \[\mathrm{Ti}^{4+}, \mathrm{Cr}^{3+}, \mathrm{V}^{3+} \] (Atomic number of $\displaystyle \mathrm{Ti}=22, \mathrm{Cr}=24, \mathrm{~V}=23$ )(ii)Why is $\displaystyle \mathrm{Mn}^{2+}$ much more resistant than $\displaystyle \mathrm{Fe}^{2+}$ towards oxidation ?(iii)Highest oxidation state of a metal is shown in its oxide or fluoride only. Justify the statement.
(i)
Which ion amongst the following is colourless and why? \[\mathrm{Ti}^{4+}, \mathrm{Cr}^{3+}, \mathrm{V}^{3+} \] (Atomic number of $\displaystyle \mathrm{Ti}=22, \mathrm{Cr}=24, \mathrm{~V}=23$ )
(ii)
Why is $\displaystyle \mathrm{Mn}^{2+}$ much more resistant than $\displaystyle \mathrm{Fe}^{2+}$ towards oxidation ?
(iii)
Highest oxidation state of a metal is shown in its oxide or fluoride only. Justify the statement.
Marking-scheme solution
(i) \(\displaystyle \mathrm{Ti}^{4+}\) no unpaired electrons in d-orbital / no d-d transition / \(\displaystyle \mathrm{d}^{0}\) configuration.
(ii) \(\displaystyle \mathrm{Mn}^{2+}\) is \(\displaystyle d^{5}\) and is more stable than \(\displaystyle \mathrm{Mn}^{3+}\left(d^{4}\right)\) whereas \(\displaystyle \mathrm{Fe}^{3+}\left(d^{5}\right)\) is more stable than \(\displaystyle \mathrm{Fe}^{2+}\left(d^{4}\right)\).
(iii) Because fluorine and oxygen are highly electronegative / both are strong oxidising agents.
The d-and f-Block ElementsGeneral Properties of the Transition Elements (d-Block)Understandshort_answermedium
More from The d-and f-Block Elements
- (i) Silver atom has completely filled d-orbitals in its ground state, it is still considered to be a…2022 · asked 3×
- (i) Describe giving reason which one of the following pairs has the property indicated: (I) Fe or Cu - higher…2026 · asked 3×
- The diamagnetic species is:2025 · asked 3×
- Assertion: Zr and Hf are of almost similar atomic radii. Reason (R): This is due to Lanthanoid contraction.2024 · asked 3×
- (i) When pyrolusite ore is fused with KOH, in presence of air, a dark green coloured product 'A' is obtained…2025 · asked 3×
- The element having [Ar] 3 d^10 4 s^1 electronic configuration is2025 · asked 3×
- From the given E^ values of the first row transition elements, answer the following questions: (i) Why is E…2022 · asked 3×
- Account for the following: (i) Transition metals and their compounds show catalytic activities. (ii) Zn, Cd…2022 · asked 3×
CBSE Class 12 Chemistry past-paper question from the 2022board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.