Ncert Solutions Chemistry Class 12th

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct option: C

The chelate effect is when a chelating ligand coordinates the stabilisation of a molecule. Any ligand that binds to metal forms a ring with 5 or 6 members, which is the most stable.

Here, CO, CN, H₂O is monodentate ligand [Fe (C₂O₄)₃]^3-  is an oxalate ligand. 

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct option:  A

Diamminedichloridoplatinum (II) is also known as azane 

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct option: D

When 1 mol [CrCl₃ (H₂O)₃]6H₂O is treated with excess of AgNO₃, 3 mol of AgCl is produced, i.e., [CrCl₃ (H₂O)₃]6H₂Ois dissociated in aqueous solution and all three chloride comes in solution.

[Cr (H₂O)₆]Cl₃→ [Cr (H₂O)₆]³⁺  + 3Cl^- 

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct option: B

When 0.1 mol CoCl₃ (NH₃)₅ is treated with excess of AgNO₃, In the given reaction [CoCl3 (NH₃)₅]Cl₂

then electrolytic solution must contain 

[CoCl₃ (NH₃)₅]Cl²⁺  and two Cl^-  ions. 

Hence, it is 1:2 electrolyte.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct option: A

Strong field ligands have five degenerate energy levels, which means they have more energy separation than weak field ligands.

Here, ΔE= $\frac{\mathrm{h}\mathrm{c}}{\mathrm{\lambda }}$

ΔE α $\frac{1}{\mathrm{\lambda }}$

$\mathrm{\lambda }$ α $\frac{1}{\mathrm{\Delta }\mathrm{E}}$

The wavelength decreases as the energy separation rises.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct options: B

The bigger the value of constant, the better will be the stability.

Here, has the highest value of logk which corresponds to the highest value of k. 

This is a Short Answer Type Questions  as classified in NCERT Exemplar

Ans: Ambidentate ligands are ligands which have two donating sites. Coordinating compounds containing ambidentate ligands show linkage isomerism due to two different binding positions. Linkage isomerism have same ligand and geometry attached to a central metal ion by different donating sites

Examples:

(i) 

(ii) M←SCN

thiocyanato

M←NCS

isothiocyanato

This is a Short Answer Type Questions  as classified in NCERT Exemplar

Ans: In CuSO₄⋅5H₂O, water acts as ligand and causes crystal field splitting. This makes d - d transitions possible. On the other hand, in CuSO₄, splitting is not possible due to the lack of ligand in the crystal field. As a result, no colour is visible.

This is a Short Answer Type Questions  as classified in NCERT Exemplar

Ans: Due to the presence of weak and strong field ligands in complexes, compounds with comparable geometry have distinct magnetic moments. The magnetic moment decreases when the CFSE increases, and vice versa.

Example: [Fe (CN)₆]^3-  - Fe³⁺ ,3d⁵, CN^-  (strong field ligand, pairs electron)

  [Fe (H2O)₆]^3-  - Fe³⁺ ,3d5, H₂O (weak field ligand, does not pair)

This is a Short Answer Type Questions  as classified in NCERT Exemplar

Ans: CFSE is higher when the complex contains strong field ligand. Thus, crystal field splitting energy increases in the order

[Cr (Cl)₆]³⁻< [Cr (NH₃)₆]³⁺< [Cr (CN)₆]^3−.

Because according to spectrochemical series the order of field strength is

Cl⁻3−