CBSE 2025 · Region 1 · Set 2 · Q32 · 5 marks
(A)For the complex $\displaystyle \left[\mathrm{Fe}(\mathrm{en})_{2} \mathrm{C} l_{2}\right] \mathrm{C} l$, identify : $\displaystyle 5$(a)the oxidation number of iron.(b)the hybridization and the shape of the complex.(c)the magnetic behaviour of the complex(d)whether there is an optical isomer of the complex ? If so draw its structure.(e)IUPAC name of the complex. (At. no. of $\displaystyle \mathrm{Fe}=26$ )OR 32. (B) (a) Using IUPAC norms write the names of the following: ( $\displaystyle \mathbf{3} \boldsymbol{+} \mathbf{2} \boldsymbol{=} \mathbf{5}$ )(i)$\displaystyle \left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}\left(\mathrm{NO}_{2}\right)\right] \mathrm{Cl}$(ii)$\displaystyle \mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$(iii)$\displaystyle \left[\mathrm{Cr}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{3}\right]^{3-}$(b)What is crystal field splitting energy ? Why low spin tetrahedral complexes are not formed ?
(A)
For the complex $\displaystyle \left[\mathrm{Fe}(\mathrm{en})_{2} \mathrm{C} l_{2}\right] \mathrm{C} l$, identify : $\displaystyle 5$
(a)
the oxidation number of iron.
(b)
the hybridization and the shape of the complex.
(c)
the magnetic behaviour of the complex
(d)
whether there is an optical isomer of the complex ? If so draw its structure.
(e)
IUPAC name of the complex. (At. no. of $\displaystyle \mathrm{Fe}=26$ )
OR 32. (B) (a) Using IUPAC norms write the names of the following: ( $\displaystyle \mathbf{3} \boldsymbol{+} \mathbf{2} \boldsymbol{=} \mathbf{5}$ )
(i)
$\displaystyle \left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}\left(\mathrm{NO}_{2}\right)\right] \mathrm{Cl}$
(ii)
$\displaystyle \mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$
(iii)
$\displaystyle \left[\mathrm{Cr}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{3}\right]^{3-}$
(b)
What is crystal field splitting energy ? Why low spin tetrahedral complexes are not formed ?
Marking-scheme solution
(A)
a) +$\displaystyle 3$
(b)
d2sp3, octahedral
(c)
Paramagnetic
(d)
Yes,
cis form
(e)
dichloridobis(ethane-$\displaystyle 1,2$-diamine)iron(III) Chloride
(B)
a) i) Tetraamminechloridonitrito-N-cobalt(III) chloride
(ii)
Potassium hexacyanidoferrate(III)
(iii)
Trioxalatochromate(III) ion
(b)
•
The energy required to split the degenerate d-orbitals into two sets of orbitals. /
The difference of energy between the two sets of d-orbitals t2g and eg due to the
presence of ligands in a definite geometry
•
The orbital splitting energies are not sufficiently large for forcing paring of
electrons.
Coordination CompoundsNomenclature of Coordination CompoundsApplylong_answerhard
More from Coordination Compounds
- The Valence Bond Theory (VBT) explains the formation, magnetic behaviour and geometrical shapes of…2024 · asked 3×
- Which of the following ligands forms a chelate complex?2026 · asked 3×
- When a coordination compound CoCl 3 · 6 NH 3 is mixed with excess of AgNO 3 solution, 3 moles of AgCl are…2026 · asked 3×
- Write the IUPAC name of the complex [Pt(en) 2 Cl 2]^2+. Draw the structure of geometrical isomer of this…2025 · asked 3×
- The nature of bonding, structure of the coordination compound can be explained to some extent by valence bond…2024 · asked 3×
- Draw the geometrical isomers of [Co(en) 2 Cl 2]^2+. Which geometrical isomer of [Co(en) 2 Cl 2]^2+ is not…2023 · asked 3×
- In coordination compounds, metals show two types of linkages, primary and secondary. Primary valencies are…2023 · asked 3×
- Answer any three of the following questions: Explain the type of hybridization in [Fe(CN) 6]^3- on the basis…2023 · asked 3×
CBSE Class 12 Chemistry past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.