(D) : $\left[\mathrm{CoF}_{6}\right]^{3-}$ has lowest $\Delta_{0}$ value because it contains the weak field ligand and weak field ligand forms the high spin complex with $3 \mathrm{~d}$-series metal. As we know that the high spin complex has lower CFSE $\left(\Delta_{\mathrm{o}}\right)$ than low spin complex.
BCECE-2018
COORDINATION COMPOUNDS
274308
According to crystal field theory, the M-L bond in a complex is
1 partially covalent
2 purely ionic
3 purely covalent
4 purely coordinate
Explanation:
(B) : According to crystal field theory (CFT), the bonding between control metal cation and is not covalent but it is regarded as purely electrostatic or purely ionic.
Karnataka-CET-2017
COORDINATION COMPOUNDS
274309
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $\mathrm{Co}^{3+}$ is
(D) : The wavelength of absorption in the visible range for the complex are depends upon the ligand field, higher the field of ligand, lower will be wavelength of absorption the ligand field ordere are $\mathrm{H}_{2} \mathrm{O}<\mathrm{NH}_{3}<$ en. Thus, the order of wavelength of absorption will be $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
NEET 2017
COORDINATION COMPOUNDS
274311
The complex ion having minimum magnitude of $\Delta_{\mathbf{0}}$ (CFSE) is
(C) : The CFSE of complex depends upon the nature of ligands, lower the field of ligand, less will be CFSE. Here, $\mathrm{Cl}$ has the less field of energy due to which it has the minimum magnitude of $\Delta_{0}$ (CFSE).
(D) : $\left[\mathrm{CoF}_{6}\right]^{3-}$ has lowest $\Delta_{0}$ value because it contains the weak field ligand and weak field ligand forms the high spin complex with $3 \mathrm{~d}$-series metal. As we know that the high spin complex has lower CFSE $\left(\Delta_{\mathrm{o}}\right)$ than low spin complex.
BCECE-2018
COORDINATION COMPOUNDS
274308
According to crystal field theory, the M-L bond in a complex is
1 partially covalent
2 purely ionic
3 purely covalent
4 purely coordinate
Explanation:
(B) : According to crystal field theory (CFT), the bonding between control metal cation and is not covalent but it is regarded as purely electrostatic or purely ionic.
Karnataka-CET-2017
COORDINATION COMPOUNDS
274309
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $\mathrm{Co}^{3+}$ is
(D) : The wavelength of absorption in the visible range for the complex are depends upon the ligand field, higher the field of ligand, lower will be wavelength of absorption the ligand field ordere are $\mathrm{H}_{2} \mathrm{O}<\mathrm{NH}_{3}<$ en. Thus, the order of wavelength of absorption will be $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
NEET 2017
COORDINATION COMPOUNDS
274311
The complex ion having minimum magnitude of $\Delta_{\mathbf{0}}$ (CFSE) is
(C) : The CFSE of complex depends upon the nature of ligands, lower the field of ligand, less will be CFSE. Here, $\mathrm{Cl}$ has the less field of energy due to which it has the minimum magnitude of $\Delta_{0}$ (CFSE).
(D) : $\left[\mathrm{CoF}_{6}\right]^{3-}$ has lowest $\Delta_{0}$ value because it contains the weak field ligand and weak field ligand forms the high spin complex with $3 \mathrm{~d}$-series metal. As we know that the high spin complex has lower CFSE $\left(\Delta_{\mathrm{o}}\right)$ than low spin complex.
BCECE-2018
COORDINATION COMPOUNDS
274308
According to crystal field theory, the M-L bond in a complex is
1 partially covalent
2 purely ionic
3 purely covalent
4 purely coordinate
Explanation:
(B) : According to crystal field theory (CFT), the bonding between control metal cation and is not covalent but it is regarded as purely electrostatic or purely ionic.
Karnataka-CET-2017
COORDINATION COMPOUNDS
274309
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $\mathrm{Co}^{3+}$ is
(D) : The wavelength of absorption in the visible range for the complex are depends upon the ligand field, higher the field of ligand, lower will be wavelength of absorption the ligand field ordere are $\mathrm{H}_{2} \mathrm{O}<\mathrm{NH}_{3}<$ en. Thus, the order of wavelength of absorption will be $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
NEET 2017
COORDINATION COMPOUNDS
274311
The complex ion having minimum magnitude of $\Delta_{\mathbf{0}}$ (CFSE) is
(C) : The CFSE of complex depends upon the nature of ligands, lower the field of ligand, less will be CFSE. Here, $\mathrm{Cl}$ has the less field of energy due to which it has the minimum magnitude of $\Delta_{0}$ (CFSE).
(D) : $\left[\mathrm{CoF}_{6}\right]^{3-}$ has lowest $\Delta_{0}$ value because it contains the weak field ligand and weak field ligand forms the high spin complex with $3 \mathrm{~d}$-series metal. As we know that the high spin complex has lower CFSE $\left(\Delta_{\mathrm{o}}\right)$ than low spin complex.
BCECE-2018
COORDINATION COMPOUNDS
274308
According to crystal field theory, the M-L bond in a complex is
1 partially covalent
2 purely ionic
3 purely covalent
4 purely coordinate
Explanation:
(B) : According to crystal field theory (CFT), the bonding between control metal cation and is not covalent but it is regarded as purely electrostatic or purely ionic.
Karnataka-CET-2017
COORDINATION COMPOUNDS
274309
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $\mathrm{Co}^{3+}$ is
(D) : The wavelength of absorption in the visible range for the complex are depends upon the ligand field, higher the field of ligand, lower will be wavelength of absorption the ligand field ordere are $\mathrm{H}_{2} \mathrm{O}<\mathrm{NH}_{3}<$ en. Thus, the order of wavelength of absorption will be $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}<\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
NEET 2017
COORDINATION COMPOUNDS
274311
The complex ion having minimum magnitude of $\Delta_{\mathbf{0}}$ (CFSE) is
(C) : The CFSE of complex depends upon the nature of ligands, lower the field of ligand, less will be CFSE. Here, $\mathrm{Cl}$ has the less field of energy due to which it has the minimum magnitude of $\Delta_{0}$ (CFSE).