(C) : Valence electron of $\mathrm{Fe}=3 \mathrm{~d}^{6} 4 \mathrm{~s}^{2}$ Lone pair of electron donated by $1 \mathrm{CO}=2 \mathrm{e}^{-}$ By $5 \mathrm{CO}=2 \times 5=10 \mathrm{e}^{-}$ Number of electron in $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]=8+10$ $=18 \mathrm{e}^{-}$ $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]$ is follow the 18 octet rule.
JIPMER-2019
COORDINATION COMPOUNDS
274194
The effective atomic number of Iron $(Z=26)$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}$ is
1 36
2 33
3 35
4 34
Explanation:
(C) : Atomic number of $\mathrm{Fe}=26$ Oxidation state of $\mathrm{Fe}$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=+3$ Number of donor atom attached with $\mathrm{Fe}=6$ $\mathrm{EAN}=$ Atomic No. - oxidation state $+2 \mathrm{x}$ (No. of donor atom attached with metal) EAN of $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=26-3+2 \times 6$ $=35$
MHT CET-03.05.2019
COORDINATION COMPOUNDS
274197
The molar ionic conductances of the octahedral complexes: (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}$ (iv) $\mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}$ Follow the order
1 i $<$ ii $<$ iii $<$ iv
2 iv $<$ iii $<$ ii $<$ i
3 iii $<$ iv $<$ ii $<$ i
4 iv $<$ iii $<$ i $<$ ii
Explanation:
(B) : Molar ionic conductance of the octahedral complex depends on the number of ions formed. Pt in + $\mathrm{Cl}$ oxidation state form complex of coordination number of 6 (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{3} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{3+}+3 \mathrm{Cl}^{-}\right.$ $\text {No of ions }=4$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}_{2} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]^{2+}+2 \mathrm{Cl}^{-}$ $\text {No of ions }=3$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right] \mathrm{Cl} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{+}+\mathrm{Cl}^{-}$ $\mathrm{No}^{\text {of ions }}=2$ $\text { (iv) } \mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{4}\right]$ $\text { No of ions }=0$
,d) Exp: (C, D) : (i) $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}$ In $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}, \mathrm{Fe}$ is present as $\mathrm{Fe}^{2+}$. $[\mathrm{CN}]^{-}$being strong field ligand, paired up the $\mathrm{d}$ electrons of the metal]. $\left[\mathrm{Fe}\left(\mathrm{CN}_{6}\right)\right]^{4-}=$ Shape Octahedral. Among the given options $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ and $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ are the octahedral complex. (ii) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ In this complex, oxidation state of cobalt is +3 and has electronic configuration $3 \mathrm{~d}^{6}$. Its hybridisation scheme can be shown as : $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (inner orbitalor Six pairs of electrons from six $\mathrm{NH}_{3}$ molecule Six pairs of electrons one from each $\mathrm{NH}_{3}$ molecule, occupy the six hybrid orbitals. Thus, complex has octahedral $\left(\mathrm{d}^{2} \mathrm{sp}^{3}\right)$ geometry. $\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]$ and $\left[\mathrm{PtCl}_{4}\right]^{2-}$ are tetrahedral and square planar respectively.
JCECE - 2018
COORDINATION COMPOUNDS
274209
The number of donor sites in dimethyl glyoxime, glycinato, diethylene triamine and EDTA are respectively:
1 2,2, 3 and 4
2 2,2,3 and 6
3 2, 2, 2 and 6
4 2, 3, 3 and 6
Explanation:
(B) : Demethyl glyoxine, has 2 donor sites Glycinato, has 3 donor sites EDTA $^{4-}$,
(C) : Valence electron of $\mathrm{Fe}=3 \mathrm{~d}^{6} 4 \mathrm{~s}^{2}$ Lone pair of electron donated by $1 \mathrm{CO}=2 \mathrm{e}^{-}$ By $5 \mathrm{CO}=2 \times 5=10 \mathrm{e}^{-}$ Number of electron in $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]=8+10$ $=18 \mathrm{e}^{-}$ $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]$ is follow the 18 octet rule.
JIPMER-2019
COORDINATION COMPOUNDS
274194
The effective atomic number of Iron $(Z=26)$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}$ is
1 36
2 33
3 35
4 34
Explanation:
(C) : Atomic number of $\mathrm{Fe}=26$ Oxidation state of $\mathrm{Fe}$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=+3$ Number of donor atom attached with $\mathrm{Fe}=6$ $\mathrm{EAN}=$ Atomic No. - oxidation state $+2 \mathrm{x}$ (No. of donor atom attached with metal) EAN of $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=26-3+2 \times 6$ $=35$
MHT CET-03.05.2019
COORDINATION COMPOUNDS
274197
The molar ionic conductances of the octahedral complexes: (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}$ (iv) $\mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}$ Follow the order
1 i $<$ ii $<$ iii $<$ iv
2 iv $<$ iii $<$ ii $<$ i
3 iii $<$ iv $<$ ii $<$ i
4 iv $<$ iii $<$ i $<$ ii
Explanation:
(B) : Molar ionic conductance of the octahedral complex depends on the number of ions formed. Pt in + $\mathrm{Cl}$ oxidation state form complex of coordination number of 6 (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{3} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{3+}+3 \mathrm{Cl}^{-}\right.$ $\text {No of ions }=4$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}_{2} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]^{2+}+2 \mathrm{Cl}^{-}$ $\text {No of ions }=3$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right] \mathrm{Cl} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{+}+\mathrm{Cl}^{-}$ $\mathrm{No}^{\text {of ions }}=2$ $\text { (iv) } \mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{4}\right]$ $\text { No of ions }=0$
,d) Exp: (C, D) : (i) $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}$ In $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}, \mathrm{Fe}$ is present as $\mathrm{Fe}^{2+}$. $[\mathrm{CN}]^{-}$being strong field ligand, paired up the $\mathrm{d}$ electrons of the metal]. $\left[\mathrm{Fe}\left(\mathrm{CN}_{6}\right)\right]^{4-}=$ Shape Octahedral. Among the given options $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ and $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ are the octahedral complex. (ii) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ In this complex, oxidation state of cobalt is +3 and has electronic configuration $3 \mathrm{~d}^{6}$. Its hybridisation scheme can be shown as : $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (inner orbitalor Six pairs of electrons from six $\mathrm{NH}_{3}$ molecule Six pairs of electrons one from each $\mathrm{NH}_{3}$ molecule, occupy the six hybrid orbitals. Thus, complex has octahedral $\left(\mathrm{d}^{2} \mathrm{sp}^{3}\right)$ geometry. $\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]$ and $\left[\mathrm{PtCl}_{4}\right]^{2-}$ are tetrahedral and square planar respectively.
JCECE - 2018
COORDINATION COMPOUNDS
274209
The number of donor sites in dimethyl glyoxime, glycinato, diethylene triamine and EDTA are respectively:
1 2,2, 3 and 4
2 2,2,3 and 6
3 2, 2, 2 and 6
4 2, 3, 3 and 6
Explanation:
(B) : Demethyl glyoxine, has 2 donor sites Glycinato, has 3 donor sites EDTA $^{4-}$,
(C) : Valence electron of $\mathrm{Fe}=3 \mathrm{~d}^{6} 4 \mathrm{~s}^{2}$ Lone pair of electron donated by $1 \mathrm{CO}=2 \mathrm{e}^{-}$ By $5 \mathrm{CO}=2 \times 5=10 \mathrm{e}^{-}$ Number of electron in $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]=8+10$ $=18 \mathrm{e}^{-}$ $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]$ is follow the 18 octet rule.
JIPMER-2019
COORDINATION COMPOUNDS
274194
The effective atomic number of Iron $(Z=26)$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}$ is
1 36
2 33
3 35
4 34
Explanation:
(C) : Atomic number of $\mathrm{Fe}=26$ Oxidation state of $\mathrm{Fe}$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=+3$ Number of donor atom attached with $\mathrm{Fe}=6$ $\mathrm{EAN}=$ Atomic No. - oxidation state $+2 \mathrm{x}$ (No. of donor atom attached with metal) EAN of $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=26-3+2 \times 6$ $=35$
MHT CET-03.05.2019
COORDINATION COMPOUNDS
274197
The molar ionic conductances of the octahedral complexes: (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}$ (iv) $\mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}$ Follow the order
1 i $<$ ii $<$ iii $<$ iv
2 iv $<$ iii $<$ ii $<$ i
3 iii $<$ iv $<$ ii $<$ i
4 iv $<$ iii $<$ i $<$ ii
Explanation:
(B) : Molar ionic conductance of the octahedral complex depends on the number of ions formed. Pt in + $\mathrm{Cl}$ oxidation state form complex of coordination number of 6 (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{3} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{3+}+3 \mathrm{Cl}^{-}\right.$ $\text {No of ions }=4$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}_{2} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]^{2+}+2 \mathrm{Cl}^{-}$ $\text {No of ions }=3$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right] \mathrm{Cl} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{+}+\mathrm{Cl}^{-}$ $\mathrm{No}^{\text {of ions }}=2$ $\text { (iv) } \mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{4}\right]$ $\text { No of ions }=0$
,d) Exp: (C, D) : (i) $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}$ In $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}, \mathrm{Fe}$ is present as $\mathrm{Fe}^{2+}$. $[\mathrm{CN}]^{-}$being strong field ligand, paired up the $\mathrm{d}$ electrons of the metal]. $\left[\mathrm{Fe}\left(\mathrm{CN}_{6}\right)\right]^{4-}=$ Shape Octahedral. Among the given options $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ and $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ are the octahedral complex. (ii) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ In this complex, oxidation state of cobalt is +3 and has electronic configuration $3 \mathrm{~d}^{6}$. Its hybridisation scheme can be shown as : $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (inner orbitalor Six pairs of electrons from six $\mathrm{NH}_{3}$ molecule Six pairs of electrons one from each $\mathrm{NH}_{3}$ molecule, occupy the six hybrid orbitals. Thus, complex has octahedral $\left(\mathrm{d}^{2} \mathrm{sp}^{3}\right)$ geometry. $\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]$ and $\left[\mathrm{PtCl}_{4}\right]^{2-}$ are tetrahedral and square planar respectively.
JCECE - 2018
COORDINATION COMPOUNDS
274209
The number of donor sites in dimethyl glyoxime, glycinato, diethylene triamine and EDTA are respectively:
1 2,2, 3 and 4
2 2,2,3 and 6
3 2, 2, 2 and 6
4 2, 3, 3 and 6
Explanation:
(B) : Demethyl glyoxine, has 2 donor sites Glycinato, has 3 donor sites EDTA $^{4-}$,
(C) : Valence electron of $\mathrm{Fe}=3 \mathrm{~d}^{6} 4 \mathrm{~s}^{2}$ Lone pair of electron donated by $1 \mathrm{CO}=2 \mathrm{e}^{-}$ By $5 \mathrm{CO}=2 \times 5=10 \mathrm{e}^{-}$ Number of electron in $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]=8+10$ $=18 \mathrm{e}^{-}$ $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]$ is follow the 18 octet rule.
JIPMER-2019
COORDINATION COMPOUNDS
274194
The effective atomic number of Iron $(Z=26)$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}$ is
1 36
2 33
3 35
4 34
Explanation:
(C) : Atomic number of $\mathrm{Fe}=26$ Oxidation state of $\mathrm{Fe}$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=+3$ Number of donor atom attached with $\mathrm{Fe}=6$ $\mathrm{EAN}=$ Atomic No. - oxidation state $+2 \mathrm{x}$ (No. of donor atom attached with metal) EAN of $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=26-3+2 \times 6$ $=35$
MHT CET-03.05.2019
COORDINATION COMPOUNDS
274197
The molar ionic conductances of the octahedral complexes: (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}$ (iv) $\mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}$ Follow the order
1 i $<$ ii $<$ iii $<$ iv
2 iv $<$ iii $<$ ii $<$ i
3 iii $<$ iv $<$ ii $<$ i
4 iv $<$ iii $<$ i $<$ ii
Explanation:
(B) : Molar ionic conductance of the octahedral complex depends on the number of ions formed. Pt in + $\mathrm{Cl}$ oxidation state form complex of coordination number of 6 (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{3} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{3+}+3 \mathrm{Cl}^{-}\right.$ $\text {No of ions }=4$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}_{2} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]^{2+}+2 \mathrm{Cl}^{-}$ $\text {No of ions }=3$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right] \mathrm{Cl} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{+}+\mathrm{Cl}^{-}$ $\mathrm{No}^{\text {of ions }}=2$ $\text { (iv) } \mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{4}\right]$ $\text { No of ions }=0$
,d) Exp: (C, D) : (i) $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}$ In $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}, \mathrm{Fe}$ is present as $\mathrm{Fe}^{2+}$. $[\mathrm{CN}]^{-}$being strong field ligand, paired up the $\mathrm{d}$ electrons of the metal]. $\left[\mathrm{Fe}\left(\mathrm{CN}_{6}\right)\right]^{4-}=$ Shape Octahedral. Among the given options $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ and $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ are the octahedral complex. (ii) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ In this complex, oxidation state of cobalt is +3 and has electronic configuration $3 \mathrm{~d}^{6}$. Its hybridisation scheme can be shown as : $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (inner orbitalor Six pairs of electrons from six $\mathrm{NH}_{3}$ molecule Six pairs of electrons one from each $\mathrm{NH}_{3}$ molecule, occupy the six hybrid orbitals. Thus, complex has octahedral $\left(\mathrm{d}^{2} \mathrm{sp}^{3}\right)$ geometry. $\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]$ and $\left[\mathrm{PtCl}_{4}\right]^{2-}$ are tetrahedral and square planar respectively.
JCECE - 2018
COORDINATION COMPOUNDS
274209
The number of donor sites in dimethyl glyoxime, glycinato, diethylene triamine and EDTA are respectively:
1 2,2, 3 and 4
2 2,2,3 and 6
3 2, 2, 2 and 6
4 2, 3, 3 and 6
Explanation:
(B) : Demethyl glyoxine, has 2 donor sites Glycinato, has 3 donor sites EDTA $^{4-}$,
(C) : Valence electron of $\mathrm{Fe}=3 \mathrm{~d}^{6} 4 \mathrm{~s}^{2}$ Lone pair of electron donated by $1 \mathrm{CO}=2 \mathrm{e}^{-}$ By $5 \mathrm{CO}=2 \times 5=10 \mathrm{e}^{-}$ Number of electron in $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]=8+10$ $=18 \mathrm{e}^{-}$ $\left[\mathrm{Fe}(\mathrm{CO})_{5}\right]$ is follow the 18 octet rule.
JIPMER-2019
COORDINATION COMPOUNDS
274194
The effective atomic number of Iron $(Z=26)$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}$ is
1 36
2 33
3 35
4 34
Explanation:
(C) : Atomic number of $\mathrm{Fe}=26$ Oxidation state of $\mathrm{Fe}$ in $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=+3$ Number of donor atom attached with $\mathrm{Fe}=6$ $\mathrm{EAN}=$ Atomic No. - oxidation state $+2 \mathrm{x}$ (No. of donor atom attached with metal) EAN of $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{-3}=26-3+2 \times 6$ $=35$
MHT CET-03.05.2019
COORDINATION COMPOUNDS
274197
The molar ionic conductances of the octahedral complexes: (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}$ (iv) $\mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}$ Follow the order
1 i $<$ ii $<$ iii $<$ iv
2 iv $<$ iii $<$ ii $<$ i
3 iii $<$ iv $<$ ii $<$ i
4 iv $<$ iii $<$ i $<$ ii
Explanation:
(B) : Molar ionic conductance of the octahedral complex depends on the number of ions formed. Pt in + $\mathrm{Cl}$ oxidation state form complex of coordination number of 6 (i) $\mathrm{PtCl}_{4} \cdot 5 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{3} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{3+}+3 \mathrm{Cl}^{-}\right.$ $\text {No of ions }=4$ (ii) $\mathrm{PtCl}_{4} \cdot 4 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}_{2} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]^{2+}+2 \mathrm{Cl}^{-}$ $\text {No of ions }=3$ (iii) $\mathrm{PtCl}_{4} \cdot 3 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right] \mathrm{Cl} \longrightarrow\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{+}+\mathrm{Cl}^{-}$ $\mathrm{No}^{\text {of ions }}=2$ $\text { (iv) } \mathrm{PtCl}_{4} \cdot 2 \mathrm{NH}_{3}:\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{4}\right]$ $\text { No of ions }=0$
,d) Exp: (C, D) : (i) $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}$ In $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4}, \mathrm{Fe}$ is present as $\mathrm{Fe}^{2+}$. $[\mathrm{CN}]^{-}$being strong field ligand, paired up the $\mathrm{d}$ electrons of the metal]. $\left[\mathrm{Fe}\left(\mathrm{CN}_{6}\right)\right]^{4-}=$ Shape Octahedral. Among the given options $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ and $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ are the octahedral complex. (ii) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ In this complex, oxidation state of cobalt is +3 and has electronic configuration $3 \mathrm{~d}^{6}$. Its hybridisation scheme can be shown as : $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (inner orbitalor Six pairs of electrons from six $\mathrm{NH}_{3}$ molecule Six pairs of electrons one from each $\mathrm{NH}_{3}$ molecule, occupy the six hybrid orbitals. Thus, complex has octahedral $\left(\mathrm{d}^{2} \mathrm{sp}^{3}\right)$ geometry. $\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]$ and $\left[\mathrm{PtCl}_{4}\right]^{2-}$ are tetrahedral and square planar respectively.
JCECE - 2018
COORDINATION COMPOUNDS
274209
The number of donor sites in dimethyl glyoxime, glycinato, diethylene triamine and EDTA are respectively:
1 2,2, 3 and 4
2 2,2,3 and 6
3 2, 2, 2 and 6
4 2, 3, 3 and 6
Explanation:
(B) : Demethyl glyoxine, has 2 donor sites Glycinato, has 3 donor sites EDTA $^{4-}$,
