Question 1: Palette 1/40

JEE Advanced 2025 MCQ

The correct order of the wavelength maxima of the absorption band in the ultraviolet-visible region for the given complexes is

A

[Co(CN)₆] ³⁻ < [Co(NH₃)₆]³⁺ < [Co(NH₃)₅(H₂O)]³⁺ < [Co(NH₃)₅(Cl)]²⁺

B

[Co(NH₃)₅(Cl)]²⁺ < [Co(NH₃)₅(H₂O)]³⁺ < [Co(NH₃)₆]³⁺ < [Co(CN)₆]³⁻

C

[Co(CN)₆]³⁻ < [Co(NH₃)₅(Cl)]²⁺ < [Co(NH₃)₅(H₂O)]³⁺ < [Co(NH₃)₆]³⁺

D

[Co(NH₃)₆]³⁺ < [Co(CN)₆]³⁻ < [Co(NH₃)₅(Cl)]²⁺ < [Co(NH₃)₅(H₂O)]³⁺

Question 2: Palette 2/40

JEE Advanced 2024 MCQ

Among the following options, select the option in which each complex in Set-I shows geometrical isomerism and the two complexes in Set-II are ionization isomers of each other.

$ \text { [en }=\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CH}_2 \mathrm{NH}_2 \text { ] } $

A

Set-I: $\left[\mathrm{Ni}(\mathrm{CO})_4\right]$ and $\left[\mathrm{PdCl}_2\left(\mathrm{PPh}_3\right)_2\right]$

Set-II: $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{SO}_4$ and $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5\left(\mathrm{SO}_4\right)\right] \mathrm{Cl}$

B

Set-I: $\left[\mathrm{Co}(\mathrm{en})\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$ and $\left[\mathrm{PdCl}_2\left(\mathrm{PPh}_3\right)_2\right]$

Set-II: $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]\left[\mathrm{Cr}(\mathrm{CN})_6\right]$ and $\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_6\right]\left[\mathrm{Co}(\mathrm{CN})_6\right]$

C

Set-I: $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_3\left(\mathrm{NO}_2\right)_3\right]$ and $\left[\mathrm{Co}(\mathrm{en})_2 \mathrm{Cl}_2\right]$

Set-II: $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{SO}_4$ and $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5\left(\mathrm{SO}_4\right)\right] \mathrm{Cl}$

D

Set-I: $\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{Cl}_2$ and $\left[\mathrm{Co}(\mathrm{en})\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$

Set-II: $\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right] \mathrm{Cl}_3$ and $\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_5 \mathrm{Cl}\right] \mathrm{Cl}_2 \cdot \mathrm{H}_2 \mathrm{O}$

Question 3: Palette 3/40

JEE Advanced 2023 MCQ

Match the electronic configurations in List-I with appropriate metal complex ions in List-II and choose the correct option.

[Atomic Number: $\mathrm{Fe}=26, \mathrm{Mn}=25, \mathrm{Co}=27$ ]

List - I	List - II
(P) $t_{2 g}^6 e_g^0$	(1) $\left[\mathrm{Fe}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}$
(Q) $t_{2 g}^3 e_g^2$	(2) $\left[\mathrm{Mn}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}$
(R) $\mathrm{e}^2 \mathrm{t}_2^3$	(3) $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]^{3+}$
(S) $t_{2 g}^4 e_g^2$	(4) $\left[\mathrm{FeCl}_4\right]^{-}$
	(5) $\left[\mathrm{CoCl}_4\right]^{2-}$

A

$\mathrm{P} \rightarrow 1 ; \mathrm{Q} \rightarrow 4 ; \mathrm{R} \rightarrow 2 ; \mathrm{S} \rightarrow 3$

B

$P \rightarrow 1 ; \mathrm{Q} \rightarrow 2 ; \mathrm{R} \rightarrow 4 ; \mathrm{S} \rightarrow 5$

C

$\mathrm{P} \rightarrow 3 ; \mathrm{Q} \rightarrow 2 ; \mathrm{R} \rightarrow 5 ; \mathrm{S} \rightarrow 1$

D

$\mathrm{P} \rightarrow 3 ; \mathrm{Q} \rightarrow 2 ; \mathrm{R} \rightarrow 4 ; \mathrm{S} \rightarrow 1$

Question 4: Palette 4/40

JEE Advanced 2023 MSQ

The complex(es), which can exhibit the type of isomerism shown by $\left[\operatorname{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Br}_2\right]$, is(are) :

[en $=\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CH}_2 \mathrm{NH}_2$ ]

A

$\left[\mathrm{Pt}(\mathrm{en})(\mathrm{SCN})_2\right]$

B

$\left[\mathrm{Zn}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$

C

$\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_4\right]$

D

$\left[\mathrm{Cr}(\mathrm{en})_2\left(\mathrm{H}_2 \mathrm{O}\right)\left(\mathrm{SO}_4\right)\right]^{+}$

Question 5: Palette 5/40

JEE Advanced 2022 MCQ

LIST-I contains metal species and LIST-II contains their properties.

List-I	List-II
(I) $\left[\mathrm{Cr}(\mathrm{CN})_{6}\right]^{4-}$	(P) $t_{2 \mathrm{g}}$ orbitals contain 4 electrons
(II) $\left[\mathrm{RuCl}_{6}\right]^{2-}$	(Q) $\mu$ (spin-only $)=4.9 \mathrm{BM}$
(III) $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$	(R) low spin complex ion
(IV) $\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$	(S) metal ion in $4+$ oxidation state
	(T) $d^{4}$ species

[Given: Atomic number of $\mathrm{Cr}=24, \mathrm{Ru}=44, \mathrm{Fe}=26$ ]

Match each metal species in LIST-I with their properties in LIST-II, and choose the correct option

A

I $\rightarrow$ R, T; II $\rightarrow$ P, S; III $\rightarrow$ Q, T; IV $\rightarrow$ P, Q

B

I $\rightarrow$ R, S; II $\rightarrow$ P, T; III $\rightarrow$ P, Q; IV $\rightarrow$ Q, T

C

I $\rightarrow$ P, R; II $\rightarrow$ R, S; III $\rightarrow$ R, T; IV $\rightarrow$ P, T

D

I $\rightarrow$ Q, T; II $\rightarrow$ S, T; III $\rightarrow$ P, T; IV $\rightarrow$ Q, R

Question 6: Palette 6/40

JEE Advanced 2021 MCQ

The calculated spin only magnetic moments of [ Cr(NH₃)₆]³⁺ and [CuF₆]3^$-$ in BM, respectively, are

(Atomic numbers of Cr and Cu are 24 and 29, respectively)

A

3.87 and 2.84

B

4.90 and 1.73

C

3.87 and 1.73

D

4.90 and 2.84

Question 7: Palette 7/40

JEE Advanced 2021 MSQ

The pair(s) of complexes wherein both exhibit tetrahedral geometry is(are)

(Note : py = pyridine)

Given : Atomic numbers of Fe, Co, Ni and Cu are 26, 27, 28 and 29, respectively)

A

[FeCl₄]^$-$ and [Fe(CO)₄]^2$-$

B

[Co(CO)₄]^$-$ and [CoCl₄]^2$-$

C

[Ni(CO)₄] and [Ni(CN)₄]^2$-$

D

[Cu(py)₄]⁺ and [Cu(CN)₄]^3$-$

Question 8: Palette 8/40

JEE Advanced 2020 MSQ

In an experiment, m grams of a compound X (gas/liquid/solid) taken in a container is loaded in a balance as shown in figure I below.

In the presence of a magnetic field, the pan with X is either deflected upwards (figure II), or deflected downwards (figure III), depending on the compound X. Identify the correct statement(s).

A

If X is H₂O(l), deflection of the pan is upwards

B

If X is K₄[Fe(CN)₆](s), deflection of the pan is upwards.

C

If X is O₂(g), deflection of the pan is downwards.

D

If X is C₆H₆(l), deflection of the pan is downwards

Question 9: Palette 9/40

JEE Advanced 2020 MSQ

Choose the correct statement(s) among the following :

A

[FeCl₄]^$-$ has tetrahedral geometry.

B

[Co(en)(NH₃)₂Cl₂]⁺ has 2 geometrical isomers.

C

[FeCl₄]^$-$ has higher spin-only magnetic moment than [Co(en)(NH₃)₂Cl₂]⁺.

D

The cobalt ion in [Co(en)(NH₃)₂Cl₂]⁺ has sp³d² hybridisation.

Question 10: Palette 10/40

JEE Advanced 2018 MCQ

Match each set of hybrid orbitals from LIST - A with complex(es) given in LIST - B

	List - A			List - B
P.	dsp2		1.	[FeF6]4-
Q.	sp3		2.	[Ti(H2O)3Cl3]
R.	sp3d2		3.	[Cr(NH3)6]3+
S.	d2sp3		4.	[FeCl4]2-
			5.	Ni(CO)4
			6.	[Ni(CN)4]2-

The correct option is

A

$P - 5;Q - 4,6;R - 2,3;S - 1$

B

$P - 5,6;Q - 4;R - 3;S - 1,2$

C

$P - 6;Q - 4,5;R - 1;S - 2,3$

D

$P - 4,6;Q - 5,6;R - 1,2;S - 3$

Question 11: Palette 11/40

JEE Advanced 2018 MSQ

The correct option(s) regarding the complex

${\left[ {Co\left( {en} \right){{\left( {N{H_3}} \right)}_3}\left( {{H_2}O} \right)} \right]^{3 + }}\,\,$ $\left( {en = {H_2}NC{H_2}C{H_2}N{H_2}} \right)$ is (are)

A

It has two geometrical isomers

B

It will have three geometrical isomers if bidentate 'en' is replaced by two cyanide ligands

C

It is paramagnetic

D

It absorbs light at longer wavelength as compared to

${\left[ {Co\left( {en} \right){{\left( {N{H_3}} \right)}_4}} \right]^{3 + }}$

Question 12: Palette 12/40

JEE Advanced 2018 MSQ

The correct statement(s) regarding the binary transition metal carbonyl compounds is(are) (Atomic numbers : $Fe = 26,Ni = 28$)

A

Total number of valence shell electrons at metal center in $Fe{\left( {CO} \right)_5}\,\,$ or $Ni{\left( {CO} \right)_4}$ is $16$

B

These are predominantly low spin in nature

C

Metal-carbon bond strengthens when the oxidation state of the metal is lowered.

D

The carbonyl $C-O$ bond weakens when the oxidation state of the metal is increased

Question 13: Palette 13/40

JEE Advanced 2017 MSQ

Addition of excess aqueous ammonia to a pink colored aqueous solution of $MC{l_2},6{H_2}O\left( X \right)$ and $N{H_4}Cl$ gives an octahedral complex $Y$ in the presence of air. In aqueous solution, complex $Y$ behaves as $1:3$ electrolyte. The reaction of $X$ with excess $HCl$ at room temperature results in the formation of a blue colored complex $Z.$ The calculated spin only magnetic moment of $X$ and $Z$ is $3.87$ $B.M.,$ whereas it is zero for complex $Y.$ Among the following options, which statement(s) is (are) correct?

A

Addition of silver nitrate to $Y$ gives only two equivalents of silver chloride

B

The hybridization of the central metal ion in $Y$ is ${d^2}s{p^3}$

C

$Z$ is a tetrahedral complex

D

When $X$ and $Z$ are in equilibrium at ${0^ \circ }C,$ the color of the solution is pink

Question 14: Palette 14/40

JEE Advanced 2016 MCQ

The geometries of the ammonia complexes of Ni²⁺, Pt²⁺ and Zn²⁺, respectively, are

A

octahedral, square planar and tetrahedral

B

square planar, octahedral and tetrahedral

C

tetrahedral, square planar and octahedral

D

octahedral, tetrahedral and square planar

Question 15: Palette 15/40

JEE Advanced 2016 MCQ

Among [Ni(CO)₄], [NiCl₄]^2$-$, [Co(NH₃)₄)Cl₂]Cl, Na₃[CoF₆], Na₂O₂ and CsO₂, the total number of paramagnetic compound is

A

2

B

3

C

4

D

5

Question 16: Palette 16/40

JEE Advanced 2014 MCQ

Match each coordination compound in List I with an appropriate pair of characteristics from List II and select the correct answer using the code given below the lists.

{en = H₂NCH₂CH₂NH₂; atomic numbers : Ti = 22, Cr = 24; Co = 27; Pt = 78}

List I		List II
P.	$[Cr{(N{H_3})_3}C{l_2}]Cl$	1.	Paramagnetic and exhibits ionisation isomerism.
Q.	$[Ti{({H_2}O)_5}Cl]{(N{O_3})_2}$	2.	Diamagnetic and exhibits cis-trans isomerism.
R.	$[Pt(en)(N{H_3})Cl]N{O_3}$	3.	Paramagnetic and exhibits cis-trans isomerism.
S.	$[Co{(N{H_3})_4}{(N{O_3})_2}]N{O_3}$	4.	Diamagnetic and exhibits ionisation isomerism.

A

P-4, Q-2, R-3, S-1

B

P-3, Q-1, R-4, S-2

C

P-2, Q-1, R-3, S-4

D

P-1, Q-3, R-4, S-2

Question 17: Palette 17/40

JEE Advanced 2013 MCQ

Consider the following complex ions : P, Q and R.

$P = {[Fe{F_6}]^{3 - }}$, $Q = {[V{({H_2}O)_6}]^{2 + }}$ and $R = {[Fe{({H_2}O)_6}]^{2 + }}$

The correct order of the complex ions, according to their spin-only magnetic moment values (in B.M.) is

A

R < Q < P

B

Q < R < P

C

R < P < Q

D

Q < P < R

Question 18: Palette 18/40

JEE Advanced 2013 MSQ

The pair(s) of coordination complexes/ions exhibiting the same kind of isomerism is(are)

A

$[Cr{(N{H_3})_5}Cl]C{l_2}$ and $[Cr{(N{H_3})_4}C{l_2}]Cl$

B

${[Co{(N{H_3})_4}C{l_2}]^ + }$ and ${[Pt{(N{H_3})_2}({H_2}O)Cl]^ + }$

C

${[CoB{r_2}C{l_2}]^{2 - }}$ and ${[PtB{r_2}C{l_{12}}]^{2 - }}$

D

$[Pt{(N{H_3})_3}](N{O_3})Cl$ and $[Pt{(N{H_3})_3}Cl]Br$

Question 19: Palette 19/40

JEE Advanced 2012 MCQ

$NiC{l_2}{\{ P{({C_2}{H_5})_2}({C_6}{H_5})\} _2}$ exhibits temperature-dependent magnetic behaviour (paramagnetic/diamagnetic). The coordination geometries of Ni²⁺ in the paramagnetic and diamagnetic states are, respectively,

A

tetrahedral and tetrahedral.

B

square planar and square planar.

C

tetrahedral and square planar.

D

square planar and tetrahedral.

Question 20: Palette 20/40

JEE Advanced 2012 MCQ

As per IUPAC nomenclature, the name of the complex $[Co{({H_2}O)_4}{(N{H_3})_2}]C{l_3}$ is

A

Tetraaquadiaminecobalt (III) chloride.

B

Tetraaquadiamminecobalt (III) chloride.

C

Diaminetetraaquacobalt (III) chloride.

D

Diamminetetraaquacobalt (III) chloride.

Question 21: Palette 21/40

JEE Advanced 2011 MCQ

Geometrical shapes of the complexes formed by the reaction of Ni²⁺ with Cl^-, CN^- and H₂O respectively are

A

octahedral, tetrahedral and square planar

B

tetrahedral, square planar and octahedral

C

square planar, tetrahedral, and octahedral

D

octahedral, square planar and octahedral

Question 22: Palette 22/40

JEE Advanced 2011 MCQ

Among the following complexes (K-P),

K₃[Fe(CN)₆] (K), [Co(NH₃)₆]Cl₃ (L), Na₃[Co(oxalate)₃] (M), [Ni(H₂O)₃]Cl₂ (N), K₂[Pt(CN)₄] (O) and [Zn(H₂O)₆(NO₃)₂] (P)

The diamagnetic complexes are

A

K, L, M, N

B

K, M, O, P

C

L, M, O, P

D

L, M, N, O

Question 23: Palette 23/40

JEE Advanced 2010 MCQ

The correct structure of ethylenediaminetetraacetic acid (EDTA) is

A

B

C

D

Question 24: Palette 24/40

JEE Advanced 2010 MCQ

The ionisation isomer of $\mathrm{[Cr(H_2O)_4Cl(NO_2)]Cl}$ is

A

$[Cr{({H_2}O)_4}({O_2}N)]C{l_2}$

B

$[Cr{({H_2}O)_4}C{l_2}](N{O_2})$

C

$[Cr{({H_2}O)_4}Cl(ONO)]Cl$

D

$[Cr{({H_2}O)_4}C{l_2}(N{O_2})]{H_2}O$

Question 25: Palette 25/40

JEE Advanced 2010 MCQ

The complex showing a spin-only magnetic moment of 2.82 B.M. is :

A

$\mathrm{Ni}(\mathrm{CO})_4$

B

$\left[\mathrm{NiCl}_4\right]^{2-}$

C

$\mathrm{Ni}\left(\mathrm{PPh}_3\right)_4$

D

$\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{2-}$

Question 26: Palette 26/40

JEE Advanced 2009 MCQ

The spin only magnetic moment value (in Bohr magneton units) of Cr(CO)$_6$ is

A

0

B

2.84

C

4.90

D

5.92

Question 27: Palette 27/40

JEE Advanced 2009 MSQ

The compound(s) that exhibit(s) geometrical isomerism is(are)

A

$\mathrm{\left[ {Pt(en)C{l_2}} \right]}$

B

$\mathrm{\left[ {Pt{{(en)}_2}} \right]C{l_2}}$

C

$\mathrm{\left[ {Pt{{(en)}_2}C{l_2}} \right]C{l_2}}$

D

$\mathrm{\left[ {Pt{{(N{H_3})}_2}C{l_2}} \right]}$

Question 28: Palette 28/40

JEE Advanced 2008 MCQ

Among the following, the coloured compound is :

A

CuCl

B

K$_3$[Cu(CN)$_4$]

C

CuF$_2$

D

[Cu(CH$_3$CH)$_4$]BF$_4$

Question 29: Palette 29/40

JEE Advanced 2008 MCQ

Both [Ni(CO)$_4$] and [Ni(CN)$_4$]$^{2-}$ are diamagnetic. They hybridisations of nickel in these complexes, respectively, are :

A

sp$^3$, sp$^3$

B

sp$^3$, dsp$^2$

C

dsp$^2$, sp$^3$

D

dsp$^2$, dsp$^2$

Question 30: Palette 30/40

JEE Advanced 2008 MCQ

The IUPAC name of [Ni(NH$_3$)$_4$] [NiCl$_4$] is :

A

Tetrachloronickel (II) - tetraamminenickel (II)

B

Tetraamminenickel (II) - tetrachloronickel (II)

C

Tetraammnenickel (II) - tetrachloronickelate (II)

D

Tetrachloronickel (II) - tetraamminenickelate (0)

Question 31: Palette 31/40

JEE Advanced 2008 MCQ

Statement 1 : [Fe(H$_2$O)$_5$NO]SO$_4$ is paramagnetic.

Statement 2 : The Fe in [Fe(H$_2$O)$_5$NO]SO$_4$ has three unpaired electrons.

A

Statement 1 is True, Statement 2 is True; Statement 2 is a CORRECT explanation for Statement 1.

B

Statement 1 is True, Statement 2 is True; Statement 2 is a NOT CORRECT explanation for Statement 1.

C

Statement 1 is True, Statement 2 is False.

D

Statement 1 is False, Statement 2 is True.

Question 32: Palette 32/40

JEE Advanced 2008 MCQ

Statement 1 : The geometrical isomers of the complex [M(NH$_3$)$_4$Cl$_2$] are optically inactive.

Statement 2 : Both geometrical isomers of the complex [M(NH$_3$)$_4$Cl$_2$] possess axis of symmetry.

A

Statement 1 is True, Statement 2 is True; Statement 2 is a CORRECT explanation for Statement 1.

B

Statement 1 is True, Statement 2 is True; Statement 2 is a NOT CORRECT explanation for Statement 1.

C

Statement 1 is True, Statement 2 is False.

D

Statement 1 is False, Statement 2 is True.

Question 33: Palette 33/40

JEE Advanced 2007 MCQ

Among the following metal carbonyl, the C-O bond order is lowest in

A

$\mathrm{[Mn(CO)_6]^+}$

B

$\mathrm{[Fe(CO)_5]}$

C

$\mathrm{[Cr(CO)_6]}$

D

$\mathrm{[V(CO)_6]^-}$

Question 34: Palette 34/40

JEE Advanced 2007 MCQ

Match the complexes in Column I with their properties listed in Column II. Indicate your answer by darkening the appropriate bubbles of the 4 $\times$ 4 matrix given in the ORS.

	Column I		Column II
(A)	$\mathrm{[Co(NH_3)_4(H_2O)_2]Cl_2}$	(P)	geometrical isomers
(B)	$\mathrm{[Pt(NH_3)_2Cl_2]}$	(Q)	paramagnetic
(C)	$\mathrm{[Co(H_2O)_5Cl]Cl}$	(R)	diamagnetic
(D)	$\mathrm{[Ni(H_2O)_6]Cl_2}$	(S)	metal ion with +2 oxidation state

A

A - (p, q, s); B - (p, r, s); C - (q, s); D - (q, s)

B

A - (q, s); B - (p, r, s); C - (q); D - (q, s)

C

A - (p, q, s); B - (p, r, s); C - (q); D - (s)

D

A - (p, q, s); B - (s); C - (q, s); D - (q)

Question 35: Palette 35/40

JEE Advanced 2006 MCQ

The IUPAC names of $\mathbf{A}$ and $\mathbf{B}$ are

A

Potassium tetracyanonickelate (II), potassium tetrachloronickelate (II).

B

Tetracyanopotassiumnickelate (II), teterachloroptassiumnickelate (II).

C

Tetracyanonickel (II), tetrachloronickel (II).

D

Potassium tetracyanonickel (II), potassium tetrachloronickel (II).

Question 36: Palette 36/40

JEE Advanced 2006 MCQ

Predict the magnetic nature of $\mathbf{A}$ and $\mathbf{B}$.

A

Both are diamagnetic.

B

A is diamagnetic and B is paramagnetic with one unpaired electron.

C

A is diamagnetic and B is paramagnetic with two unpaired electrons.

D

Both are paramagnetic.

Question 37: Palette 37/40

JEE Advanced 2006 MCQ

The hybridisation of $A$ and $B$ are :

A

$d s p^2, s p^3$

B

$s p a, s p^3$

C

$d s p^2, d s p$

D

$s p^3 d^2, d^2 s p^3$

Question 38: Palette 38/40

JEE Advanced 2006 MCQ

If the bond length of CO bond in carbon monoxide is $1.128 \mathop {\rm{A}}\limits^{\rm{o}}$, then what is the value of CO bond length in $\mathrm{Fe}(\mathrm{CO})_5$?

A

$1.15 \mathop {\rm{A}}\limits^{\rm{o}}$

B

$1.128\mathop {\rm{A}}\limits^{\rm{o}}$

C

$1.72 \mathop {\rm{A}}\limits^{\rm{o}}$

D

$1.118\mathop {\rm{A}}\limits^{\rm{o}}$

Question 39: Palette 39/40

JEE Advanced 2004 MCQ

The pair of compounds having metals in their highest oxidation state is

A

MnO₂, FeCl₃

B

[MnO₄]^-, CrO₂Cl₂

C

[Fe(CN)₆]^3-, [Co(CN)₃]

D

[NiCl₄]^2- , [CoCl₄]^-

Question 40: Palette 40/40

JEE Advanced 1987 MCQ

The brown ring complex compound is formulated as [Fe(H₂O)₅(NO)⁺]SO₄. The oxidation state of iron is

A

1

B

2

C

3

D

0