JEE Mains JEE Advance BITSAT
JEE Mains | PYQ

Year

All years 2026 2025 2024 2023 2022 2021

Consider the following metal complexes: $ [\mathrm{Co(NH_3)_6}]^{3+} \quad [\mathrm{CoCl(NH_3)_5}]^{2+} \quad [\mathrm{Co(CN)_6}]^{3-} \quad [\mathrm{Co(NH_3)_5(H_2O)}]^{3+} $ The spin-only magnetic moment value of the complex that absorbs light with shortest wavelength is ________ B.M. (Nearest integer)

Three moles of $ \mathrm{AgCl} $ get precipitated when one mole of an octahedral co-ordination compound with empirical formula $ \mathrm{CrCl_3 \cdot 3NH_3 \cdot 3H_2O} $ reacts with excess of silver nitrate. The number of chloride ions satisfying the secondary valency of the metal ion is __________.

Given below are two statements:
Statement (I) : A solution of $ [\mathrm{Ni}(\mathrm{H_2O})_6]^{2+} $ is green in colour.
Statement (II) : A solution of $ [\mathrm{Ni}(\mathrm{CN})_4]^{2-} $ is colourless.
In the light of the above statements, choose the most appropriate answer from the options given below:

$ 3 $ moles of metal complex with formula $ \mathrm{Co(en)_2Cl_3} $ gives $ 3 $ moles of silver chloride on treatment with excess of silver nitrate. The secondary valency of Co in the complex is: ___________. (Round off to the Nearest Integer).

$ [\mathrm{Fe(CN)_6}]^{4-} $
$ [\mathrm{Fe(CN)_6}]^{3-} $
$ [\mathrm{Ti(CN)_6}]^{3-} $
$ [\mathrm{Ni(CN)_4}]^{2-} $
$ [\mathrm{Co(CN)_6}]^{3-} $
Among the given complexes, number of paramagnetic complexes is __________.

The conditions and consequence that favours the $ t_{2g}^3 e_g^1 $ configuration in a metal complex are:

The calculated spin-only magnetic moments of $ \mathrm{K_{3}[Fe(OH)_{6}]} $ and $ \mathrm{K_{4}[Fe(OH)_{6}]} $ respectively are:

Match List I with List II.

List I	List II
Coordination Complex	Number of unpaired electrons
A $ [\mathrm{Cr}(\mathrm{CN})_6]^{3-} $	I $ 0 $
B $ [\mathrm{Fe}(\mathrm{H}_2\mathrm{O})_6]^{2+} $	II $ 3 $
C $ [\mathrm{Co}(\mathrm{NH}_3)_6]^{3+} $	III $ 2 $
D $ [\mathrm{Ni}(\mathrm{NH}_3)_6]^{2+} $	IV $ 4 $

Choose the correct answer from the options given below :

When Ethane-$ 1,2 $-diamine is added progressively to an aqueous solution of Nickel ($ II $) chloride, the sequence of colour change observed will be:

10.

In which of the following complexes the CFSE, $ \Delta_{0} $ will be equal to zero?

11.

Arrange the following Cobalt complexes in the order of increasing Crystal Field Stabilization Energy (CFSE) value.

Choose the correct option:

12.

Given below are two statements:
Statement-I: $ \mathrm{[Ni(CN)_4]^{2-}} $ is square planar and diamagnetic complex, with $ \mathrm{dsp^2} $ hybridization for Ni but $ \mathrm{[Ni(CO)_4]} $ is tetrahedral, paramagnetic and with $ \mathrm{sp^3} $-hybridization of Ni.
Statement-II: $ \mathrm{[NiCl_4]^{2-}} $ and $ \mathrm{[Ni(CO)_4]} $ both have same d-electron configuration, have same geometry and are paramagnetic.
In light of the above statements, choose the correct answer form the options given below:

13.

An octahedral complex with the formula $ \mathrm{CoCl_3} \cdot n\mathrm{NH_3} $ upon reaction with excess of $ \mathrm{AgNO_3} $ solution gives $ 2 \, \text{moles} $ of $ \mathrm{AgCl} $. Consider the oxidation state of Co in the complex is ‘$ x $’. The value of ‘‘$ x + n $’’ is ______.

14.

An ammoniacal metal salt solution gives a brilliant red precipitate on addition of dimethylglyoxime. The metal ion is:

15.

Number of ambidentate ligands among the following is _______.
$ \mathrm{NO_2^-} $, $ \mathrm{SCN^-} $, $ \mathrm{C_2O_4^{2-}} $, $ \mathrm{NH_3} $, $ \mathrm{CN^-} $, $ \mathrm{SO_4^{2-}} $, $ \mathrm{H_2O} $.

16.

Match List – I with List – II

List I (Complex ion)	List – II (Spin only magnetic moment in B.M.)
(A) $ [\mathrm{Cr(NH_3)_6}]^{3+} $	(I) $ 4.90 $
(B) $ [\mathrm{NiCl_4}]^{2-} $	(II) $ 3.87 $
(C) $ [\mathrm{CoF_6}]^{3-} $	(III) $ 0.0 $
(D) $ [\mathrm{Ni(CN)_4}]^{2-} $	(IV) $ 2.83 $

Choose the correct answer from the options given below :

17.

The coordination geometry around the manganese in decacarbonyldimanganese $ (0) $ is:

18.

The type of hybridisation and magnetic property of the complex $ [\mathrm{MnCl_6}]^{3-} $, respectively, are:

19.

Number of complexes from the following with even number of unpaired “$ d $” electrons is ______.
$ [\mathrm{V}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Cr}(\mathrm{H_2O})_6]^{2+};\ [\mathrm{Fe}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Ni}(\mathrm{H_2O})_6]^{3+};\ [\mathrm{Cu}(\mathrm{H_2O})_6]^{2+} $
[Given atomic numbers : $ \mathrm{V}=23 $, $ \mathrm{Cr}=24 $, $ \mathrm{Fe}=26 $, $ \mathrm{Ni}=28 $, $ \mathrm{Cu}=29 $]

20.

The spin only magnetic moment of $ [\mathrm{Mn}(\mathrm{H_2O})_6]^{2+} $ complexes is ______ B.M. $[\text{Nearest integer}]$
$\text{Given: Atomic number of Mn is } 25$.

21.

The spin only magnetic moment value of square planar complex $ [\mathrm{Pt}(\mathrm{NH}_3)_2\mathrm{Cl(NH_2CH_3})]\mathrm{Cl} $ is __________ B.M (Nearest integer)
(Given atomic number for Pt = $ 78 $)

22.

Match List I with List II.

List I Complex	List II CFSE($ \Delta_0 $)
A. $ [\text{Cu}(\text{NH}_3)_6]^{2+} $	I. $ -0.6 $
B. $ [\text{Ti}(\text{H}_2\text{O})_6]^{3+} $	II. $ -2.0 $
C. $ [\text{Fe}(\text{CN})_6]^{3-} $	III. $ -1.2 $
D. $ [\text{NiF}_6]^{4-} $	IV. $ -0.4 $

Choose the correct answer from the options given below:

23.

Which one of the following complexes will have $ \Delta_{0} = 0 $ and $ \mu = 5.96 \, \text{B.M} $?

24.

The number of unpaired $ d $-electrons in $ [\mathrm{Co}(\mathrm{H}_2\mathrm{O})_6]^{3+} $ is __________.

25.

Which of the following complex is octahedral, diamagnetic and the most stable?

26.

Identify from the following species in which $ d^2sp^3 $ hybridization is shown by central atom:

27.

The overall stability constant of the complex ion $ [\mathrm{Cu}(\mathrm{NH}_{3})_{4}]^{2+} $ is $ 2.1 \times 10^{13} $. The overall dissociation constant is $ y \times 10^{-14} $. Then $ y $ is _______. (Nearest integer)

28.

The number of geometrical isomers possible in triamminenitritocobalt $ (\text{III}) $ is $ X $ and in trioxalatochromate $ (\text{III}) $ is $ Y $. Then the value of $ X + Y $ is ________.

29.

Consider the following complexes $ [\mathrm{CoCl(NH_3)_5}]^{2+} $, $ [\mathrm{Co(CN)_6}]^{3-} $, $ [\mathrm{Co(NH_3)_5(H_2O)}]^{3+} $, $ [\mathrm{Cu(H_2O)_4}]^{2+} $.
The correct order of $ A $, $ B $, $ C $ and $ D $ in terms of wavenumber of light absorbed is:

30.

The number of complexes from the following with no electrons in the $ t_2 $ orbital is ________.
$ \mathrm{TiCl_4, [ MnO_4]^{-}, [ FeO_4]^{2-}, [ FeCl_4]^{-}, [ CoCl_4]^{2-}} $

31.

Match the List-I with List-II:

Choose the correct answer from the options given below:

32.

The set which does not have ambidentate ligand(s) is:

33.

Which of the following complex has a possibility to exist as meridional isomer?

34.

Given below are two statements:
Statement I: Crystal Field Stabilization Energy (CFSE) of $ [\text{Cr}(\text{H}_2\text{O})_6]^{2+} $ is greater than that of $ [\text{Mn}(\text{H}_2\text{O})_6]^{2+}. $.
Statement II: Potassium ferricyanide has a greater spin-only magnetic moment than sodium ferrocyanide.
In the light of the above statements, choose the correct answer from the options given below:

35.

The crystal field splitting energy of $ [Co(oxalate)_3]^{3-} $ complex is $ n $ times that of the $ [Cr(oxalate)_3]^{3-} $ complex. Here $ n $ is ______. [Assume $ \Delta_o \gg P $]

36.

Which of the following are the example of double salt?
A. $ \mathrm{FeSO_4\cdot (NH_4)_2 SO_4\cdot 6H_2O} $
B. $ \mathrm{CuSO_4\cdot 4NH_3\cdot H_2O} $
C. $ \mathrm{K_2SO_4\cdot Al_2(SO_4)_3\cdot 24H_2O} $
D. $ \mathrm{Fe(CN)_2\cdot 4KCN} $
Choose the correct answer:

37.

The conductivity of a solution of complex with formula $ \mathrm{CoCl_3(NH_3)_4} $ corresponds to $ 1:1 $ electrolyte, then the primary valency of central metal ion is _______.

38.

Given below are two statements one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): $ [\mathrm{CoCl(NH_3)_5}]^{2+} $ absorbs at lower wavelength of light with respect to $ [\mathrm{Co(NH_3)_5(H_2O)}]^{3+} $
Reason (R): It is because the wavelength of the light absorbed depends on the oxidation state of the metal ion.
In the light of the above statements choose the correct answer from the options given below:

39.

The total number of stereoisomers for the complex $ \mathrm{[Cr(ox)_2ClBr]^{3-}} $ (where $ \text{ox} = \text{oxalate} $) is:

40.

Total number of unpaired electrons present in the central metal atom/ions of $ \text{Ni(CO)}_4 $, $ [\text{NiCl}_4]^{2-} $, $ \text{PtCl}_2(\text{NH}_3)_2 $, $ [\text{Ni(CN)}_4]^{2-} $ and $ [\text{Pt(CN)}_4]^{2-} $ is __________.

41.

$ X $ is the number of geometrical isomers exhibited by $ [\mathrm{Pt(NH_3)(H_2O)BrCl}] $.
$ Y $ is the number of optically inactive isomer(s) exhibited by $ [\mathrm{CrCl_2(ox)_2}]^{3-} $.
$ Z $ is the number of geometrical isomers exhibited by $ [\mathrm{Co(NH_3)_3(NO_2)_3}] $.
The value of $ X + Y + Z $ is ____________.

42.

The d-orbital electronic configuration of the complex among $ [\mathrm{Co(en)_3}]^{3+} $, $ [\mathrm{CoF_6}]^{3-} $, $ [\mathrm{Mn(H_2O)_6}]^{2+} $ and $ [\mathrm{Zn(H_2O)_6}]^{2+} $ that has the highest CFSE is:

43.

Consider the transition metal ions $ \mathrm{Mn^{3+}} $, $ \mathrm{Cr^{3+}} $, $ \mathrm{Fe^{3+}} $ and $ \mathrm{Co^{3+}} $ and all form low spin octahedral complexes. The correct decreasing order of unpaired electrons in their respective $ d $-orbitals of the complexes is:

44.

The major product $ (P) $ in the reaction

45.

Match List-I with List-II.

Choose the correct answer from the options given below:

46.

The magnetic moment is measured in Bohr Magneton $ (\text{BM}) $
Spin only magnetic moment of Fe in $ [\text{Fe}(\text{H}_2\text{O})_6]^{3+} $ and $ [\text{Fe}(\text{CN})_6]^{3-} $ complexes respectively is:

47.

The correct IUPAC name of $ [\mathrm{PtBr}_2(\mathrm{PMe}_3)_2] $ is:

48.

The number of paramagnetic metal complex species among d$ \left[\mathrm{Co(NH_3)_6}\right]^{3+}, \left[\mathrm{Co(C_2O_4)_3}\right]^{3-}, \left[\mathrm{MnCl_6}\right]^{3-}, \left[\mathrm{Mn(CN)_6}\right]^{3-}, \left[\mathrm{CoF_6}\right]^{3-}, \left[\mathrm{Fe(CN)_6}\right]^{3-} $ and $ \left[\mathrm{FeF_6}\right]^{3-} $ with same number of unpaired electrons is ________.

49.

What amount of bromine will be required to convert $ 2 \ \text{g} $ of phenol into $ 2,4,6 $-tribromophenol?
(Given molar mass in $ \text{g mol}^{-1} $ of C, H, O, Br are $ 12 $, $ 1 $, $ 16 $, $ 80 $ respectively)

50.

From the magnetic behaviour of $ [\mathrm{NiCl_4}]^{2-} $ (paramagnetic) and $ [\mathrm{Ni(CO)_4}] $ (diamagnetic), choose the correct geometry and oxidation state.

51.

Consider the metal complexes $ [\mathrm{Ni}(\mathrm{en})_{3}]^{2+} $ ($ A $), $ [\mathrm{NiCl}_{4}]^{2-} $ ($ B $) and $ [\mathrm{Ni}(\mathrm{NH}_{3})_{6}]^{2+} $ ($ C $). Choose the CORRECT option by considering the number of unpaired electrons present in $ (A) $, $ (B) $ and $ (C) $ respectively and the order of frequency of absorption.

52.

$ [\mathrm{Co(NH_3)_6}]^{3+} $ and $ [\mathrm{CoF_6}]^{3-} $ are respectively known as:

53.

Sum of oxidation state (magnitude) and coordination number of cobalt in $ \text{Na[Co(bpy)Cl}_4] $ _______.

54.

The number of optical isomers exhibited by the iron complex $ (A) $ obtained from the following reaction is __________.
$ \mathrm{FeCl_3} + \mathrm{KOH} + \mathrm{H_2C_2O_4} \rightarrow A $

55.

The difference between spin only magnetic moment values of $ [\text{Co(H}_2O)_6]\text{Cl}_2 $ and $ [\text{Cr(H}_2O)_6]\text{Cl}_3 $ is __________.

56.

Identify the homoleptic complex(es) that is/are low spin.
(A) $ \left[\mathrm{Fe}(\mathrm{CN})_5\mathrm{NO}\right]^{2-} $ (B) $ \left[\mathrm{CoF}_6\right]^{3-} $ (C) $ \left[\mathrm{Fe}(\mathrm{CN})_6\right]^{4-} $ (D) $ \left[\mathrm{Cr}(\mathrm{H}_2\mathrm{O})_6\right]^{2+} $ (E) $ \left[\mathrm{Co}(\mathrm{NH}_3)_6\right]^{3+} $

57.

Given below are two statements.
Statement I: In $ \mathrm{CuSO_4 \cdot 5H_2O} $, Cu – O bonds are present.
Statement II: In $ \mathrm{CuSO_4 \cdot 5H_2O} $, ligands coordinating with $ \mathrm{Cu(II)} $ ion are O – and S – based ligands.
In the light of the above statement, choose the correct answer from the options given below:

58.

Compound $ A $ reacts with $ \mathrm{NH_4Cl} $ and forms a compound $ B $. Compound $ B $ reacts with $ \mathrm{H_2O} $ and excess of $ \mathrm{CO_2} $ to form compound $ C $ which on passing through or reaction with saturated $ \mathrm{NaCl} $ solution forms sodium hydrogen carbonate. Compound $ A $, $ B $ and $ C $, are respectively.

59.

The volume (in $ \text{mL} $) of $ 0.1 \ \text{M} $ $ \text{AgNO}_3 $ required for complete precipitation of chloride ions present in $ 20 \ \text{mL} $ of $ 0.01 \ \text{M} $ solution of $ [\text{Cr}(\text{H}_2\text{O})_5\text{Cl}]\text{Cl}_2 $ as silver chloride is ________.

60.

If the CFSE of $ [\mathrm{Ti(H_2O)_6}]^{3+} $ is $ -96.0 \, \mathrm{kJ/mol} $, this complex will absorb maximum at wavelength __________ nm. (Nearest integer)
Assume Planck’s constant $ (h) = 6.4 \times 10^{-34} \, \mathrm{Js} $, Speed of light $ (c) = 3.0 \times 10^{8} \, \mathrm{m/s} $ and Avogadro’s Constant $ (N_A) = 6 \times 10^{23} \, / \, \mathrm{mol} $.

61.

The total number of unpaired electrons present in $ [\mathrm{Co(NH_3)_6}]\mathrm{Cl}_2 $ and $ [\mathrm{Co(NH_3)_6}]\mathrm{Cl}_3 $ is:

62.

The correct order of the complexes $ [\mathrm{Co(NH_3)_5(H_2O)}]^{3+} (A), [\mathrm{Co(NH_3)_6}]^{3+} (B), [\mathrm{Co(CN)_6}]^{3-} (C) $ and $ [\mathrm{CoCl(NH_3)_5}]^{2+} (D) $ in terms of wavelength of light absorbed is:

63.

Arrange the following metal complex/compounds in the increasing order of spin only magnetic moment. Presume all the three, high spin system. (Atomic numbers $ \mathrm{Ce} = 58 $, $ \mathrm{Gd} = 64 $ and $ \mathrm{Eu} = 63 $.)
(a) $ (\mathrm{NH_4})_2[\mathrm{Ce}(\mathrm{NO_3})_6] $ (b) $ \mathrm{Gd}(\mathrm{NO_3})_3 $ and (c) $ \mathrm{Eu}(\mathrm{NO_3})_3 $
Answer is:

64.

The octahedral diamagnetic low spin complex among the following is:

65.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: In the complex $ (\mathrm{Ni}(\mathrm{CO})_4 $ and $( \mathrm{Fe}(\mathrm{CO})_5 $ the metals have zero oxidation state.
Reason R: Low oxidation states are found when a complex has ligands capable of $ \pi $ – donor character in addition to the $ \sigma $-bonding.
In the light of the above statements, choose the most appropriate answer from the options given below

66.

Which of the following cannot be explained by crystal field theory?

67.

$ 5.33 \; \text{g} $ of $ \text{CrCl}_3\cdot 6\text{H}_2\text{O} $, which is a $ 1:3 $ electrolyte, is dissolved in water and is passed through a cation exchanger. The chloride ions in the eluted solution, on treatment with $ \text{AgNO}_3 $ results in $ 8.61 \; \text{g} $ of $ \text{AgCl} $. The ratio of moles of complex reacted and moles of $ \text{AgCl} $ formed is ________ $ \times 10^{-2} $. (Nearest integer)
[Molar mass in $ \text{g mol}^{-1} $ Cr: $ 52 $, Ag: $ 108 $, Cl: $ 35.5 $, H: $ 1 $, O: $ 16 $]

68.

Which one of the following complexes is violet in colour?

69.

Which one of the following species responds to an external magnetic field?

70.

The number of unpaired electrons responsible for the paramagnetic nature of the following complex species are respectively:
$[Fe(CN)_6]^{3-}, [FeF_6]^{3-}, [CoF_6]^{3-}, [Mn(CN)_6]^{3-}$

71.

A transition metal $ (M) $ among $ \mathrm{Mn} $, $ \mathrm{Cr} $, $ \mathrm{Co} $ and $ \mathrm{Fe} $ has the highest standard electrode potential $ (M^{3+} / M^{2+}) $. It forms a metal complex of the type $ [M(CN)_6]^{4-} $. The number of electrons present in the $ e_g $ orbital of the complex is ____________.

72.

Spin only magnetic moment of an octahedral complex of $ \mathrm{Fe^{2+}} $ in the presence of a strong field ligand in $ \text{BM} $ is:

73.

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): The total number of geometrical isomers shown by $ [\text{Co(en)}_2 \text{Cl}_2]^+ $ complex ion is three.
Reason (R): $ [\text{Co(en)}_2 \text{Cl}_2]^+ $ complex ion has an octahedral geometry.
In the light of the above statements, choose the most appropriate answer from the options given below:

74.

Correct order of spin only magnetic moment of the following complex ions is:
(Given At. No. $ \mathrm{Fe}: 26, \ \mathrm{Co}: 267 $)

75.

Number of complexes with even number of electrons in $ t_{2g} $ orbitals is:
$ [\mathrm{Fe}(\mathrm{H}_2\mathrm{O})_6]^{2+} $, $ [\mathrm{Co}(\mathrm{H}_2\mathrm{O})_6]^{2+} $, $ [\mathrm{Co}(\mathrm{H}_2\mathrm{O})_6]^{3+} $, $ [\mathrm{Cu}(\mathrm{H}_2\mathrm{O})_6]^{2+} $, $ [\mathrm{Cr}(\mathrm{H}_2\mathrm{O})_6]^{2+} $

76.

Given below are two statements:
Statement I: Hybridisation, shape and spin only magnetic moment of $ \mathrm{K_3[Co(CO_3)_3]} $ is $ \mathrm{sp^3 d^2} $, octahedral and $ 4.9 \, \text{BM} $ respectively.
Statement II: Geometry, hybridisation and spin only magnetic moment values (BM) of the ions $ \left[ \mathrm{Ni(CN)_4} \right]^{2-} $, $ \left[ \mathrm{MnBr_4} \right]^{2-} $ and $ \left[ \mathrm{CoF_6} \right]^{3-} $ respectively are square planar, tetrahedral, octahedral; $ \mathrm{dsp^2} $, $ \mathrm{sp^3} $, $ \mathrm{sp^3 d^2} $ and $ 0 $, $ 5.9 $, $ 4.9 $.
In the light of the above statements, choose the correct answer from the options given below :

77.

The complex with highest magnitude of crystal field splitting energy $ (\Delta_0) $ is:

78.

Given below are two statements:
Statement I : A homoleptic octahedral complex, formed using monodentate ligands, will not show stereoisomerism.
Statement II : cis- and trans-platin are heteroleptic complexes of Pd.
In the light of the above statements, choose the correct answer from the options given below:

79.

Which one of the following molecules does not show stereo isomerism?

80.

The potassium ferrocyanide solution gives a Prussian blue colour, when added to:

81.

The crystal field stabilization energy (CFSE) and magnetic (spin-only) of an octahedral aqua complex of a metal ion $ (M^{z+}) $ are $ -0.8\,\Delta_0 $ and $ 3.87\,\text{BM} $, respectively. Identify $ (M^{Z+}) $:

82.

$ (a) \\ \mathrm{CoCl_3 \cdot 4 \\ NH_3} $
$ (b) \\ \mathrm{CoCl_3 \cdot 5NH_3} $
$ (C) \\ \mathrm{CoCl_3 \cdot 6NH_3} $ and
$ (d) \\ \mathrm{CoCl(NO_3)_2 \cdot 5NH_3} $
Number of complex(es) which will exist in cis-trans form is/are __________.

83.

The ‘Spin only’ Magnetic moment for $ [\text{Ni(NH}_3\text{)}_6]^{2+} $ is ______ $ \times 10^{-1} \, \text{BM} $.
(given = Atomic number of Ni : $ 28 $)

84.

The correct statements from following are:
A. The strength of anionic ligands can be explained by crystal field theory.
B. Valence bond theory does not give a quantitative interpretation of kinetic stability of coordination compounds.
C. The hybridization involved in formation of $ \mathrm{[Ni(CN)_4]^{2-}} $ complex is $ dsp^2 $.
D. The number of possible isomer(s) of cis-$ \mathrm{[PtCl_2(en)_2]^{2+}} $ is $ one $.
Choose the correct answer from the options given below:

85.

The correct statement among the following is:

86.

Given below are two statements:
Statement I: $ [\mathrm{Mn(CN)_6}]^{3-} $, $ [\mathrm{Fe(CN)_6}]^{3-} $ and $ [\mathrm{Co(C_2O_4)_3}]^{3-} $ are $ d^2sp^3 $ hybridized.
Statement II: $ [\mathrm{MnCl_6}]^{3-} $ and $ [\mathrm{FeF_6}]^{3-} $ are paramagnetic and have $ 4 $ and $ 5 $ unpaired electrons, respectively.
In the light of the above statements, choose the correct answer from the options given below:

87.

The observed magnetic moment of the complex $ [\mathrm{Mn}(\mathrm{NCS})_6]^{x-} $ is $ 6.06 \, \mathrm{BM} $. The numerical value of $ x $ is _______.

88.

An excess of $ \mathrm{AgNO_3} $ is added to $ 100 \, \mathrm{mL} $ of a $ 0.05 \, \mathrm{M} $ solution of tetraaquadichloridochromium(III) chloride. The number of moles of $ \mathrm{AgCl} $ precipitated will be ______ $ \times 10^{-3} $. (Nearest Integer)

89.

Given below are two statements:
Statement-I: $[\mathrm{CoBr}_{4}]^{2-} $ ion will absorb light of lower energy than $[\mathrm{CoCl}_{4}]^{2-} $ ion.
Statement-II: In $[\mathrm{CoI}_{4}]^{2-} $ ion, the energy separation between the two set of d-orbitals is more than $[\mathrm{CoCl}_{4}]^{2-} $ ion.
In the light of the above statements, choose the correct answer from the options given below:

90.

Among $ \mathrm{Co^{3+}} $, $ \mathrm{Ti^{2+}} $, $ \mathrm{V^{2+}} $ and $ \mathrm{Cr^{2+}} $ ions, one if used as a reagent cannot liberate $ \mathrm{H_2} $ from dilute mineral acid solution, its spin-only magnetic moment is gaseous state is ______ B.M. (Nearest integer)

91.

Match List I and List II :

Options :

92.

Identify the diamagnetic octahedral complex ions from below:
(A) $ [\mathrm{Mn(CN)_6}]^{3-} $
(B) $ [\mathrm{Co(NH_3)_6}]^{3+} $
(C) $ [\mathrm{Fe(CN)_6}]^{4-} $
(D) $ [\mathrm{Co(H_2O)_3F_3}] $
Choose the correct answer from the options given below:

93.

Number of complexes which show optical isomerism among the following is _______.
$ \text{cis-}[\mathrm{Cr(ox)_2Cl_2}]^{3-},\ [\mathrm{Co(en)_3}]^{3+},\ \text{cis-}[\mathrm{Pt(en)_2Cl_2}]^{2+},\ \text{cis-}[\mathrm{Co(en)_2Cl_2}]^{+},\ \text{trans-}[\mathrm{Pt(en)_2Cl_2}]^{2+},\ \text{trans-}[\mathrm{Cr(ox)_2Cl_2}]^{3-} $

94.

Low oxidation state of metals in their complexes are common when ligands:

95.

The primary and secondary valencies of cobalt respectively in $ [\mathrm{Co(NH_3)_5Cl}]\mathrm{Cl_2} $, are :

96.

$ \mathrm{FeO_4^{2-}} \; \overset{+2.0\,\text{V}}{\longrightarrow} \; \mathrm{Fe^{3+}} \; \overset{0.8\,\text{V}}{\longrightarrow} \; \mathrm{Fe^{2+}} \; \overset{-0.5\,\text{V}}{\longrightarrow} \; \mathrm{Fe^0} $
In the above diagram, the standard electrode potentials are given in volts (over the arrow).

97.

The number of paramagnetic complexes among $ [\mathrm{FeF}_6]^{3-} $, $ [\mathrm{Fe}(\mathrm{CN})_6]^{3-} $, $ [\mathrm{Mn}(\mathrm{CN})_6]^{3-} $, $ [\mathrm{Co}(\mathrm{C}_2\mathrm{O}_4)_3]^{3-} $, $ [\mathrm{MnCl}_6]^{3-} $ and $ [\mathrm{CoF}_6]^{3-} $, which involved $ d^{2}sp^{3} $ hybridization is ________.

98.

The correct statements about metal carbonyls are
A. The metal-carbon bonds in metal carbonyls possess both $ \sigma $ and $ \pi $-character.
B. Due to synergic bonding interactions between metal and $ \mathrm{CO} $ ligand, the metal-carbon bond becomes weak.
C. The metal-carbon $ \sigma $ bond is formed by the donation of lone pair of electrons on the carbonyl carbon into a vacant orbital of metal.
D. The metal-carbon $ \pi $ bond is formed by the donation of electrons from filled d-orbital of metal into vacant $ \pi^* $ orbital of $ \mathrm{CO} $.
Choose the correct answer from the options given below:

99.

Spin only magnetic moment of $ [\text{MnBr}_6]^{4-} $ is ______ B.M. (round off nearest integer)

100.

Identify the homoleptic complexes with odd number of $ d $ electrons in the central metal:
(A) $ [\mathrm{FeO_{4}}]^{2-} $ (B) $ [\mathrm{Fe(CN)_{6}}]^{3-} $ (C) $ [\mathrm{Fe(CN)_{5}NO}]^{2-} $ (D) $ [\mathrm{CoCl_{4}}]^{2-} $ (E) $ [\mathrm{Co(H_{2}O)_{3}F_{3}}] $
Choose the correct answer from the options given below:

101.

The $ \mathrm{Cl\!-\!Co\!-\!Cl} $ bond angle values in a $ \mathrm{fac\!-\![Co(NH_3)_3Cl_3]} $ complex is(are):

102.

The IUPAC name of $ \mathrm{K}_3[\mathrm{Co}(\mathrm{C}_2\mathrm{O}_4)_3] $ is:

103.

Number of ambidentate ligands in a representative metal complex $ [\text{M}(\text{en})(\text{SCN})_{4}] $ is __________. [en = ethylenediamine]

104.

Given below are two statements:
Statement-I: $ \mathrm{N}(\mathrm{CH}_3)_3 $ and $ \mathrm{P}(\mathrm{CH}_3)_3 $ can act as ligands to form transition metal complexes.
Statement-II: As $ \mathrm{N} $ and $ \mathrm{P} $ are from same group, the nature of bonding of $ \mathrm{N}(\mathrm{CH}_3)_3 $ and $ \mathrm{P}(\mathrm{CH}_3)_3 $ is always same with transition metals.
In the light of the above statements, choose the most appropriate answer from the options given below:

105.

An aqueous solution of $ \text{NiCl}_2 $ was heated with excess sodium cyanide in presence of strong oxidizing agent to form $ [\text{Ni}(\text{CN})_6]^{2-} $. The total change in number of unpaired electrons on metal centre is ________.

106.

Reaction of $ [\text{Co}(\text{H}_2\text{O})_6]^{2+} $ with excess ammonia and in the presence of oxygen results into a diamagnetic product. Number of electrons present in $ t_{2g} $-orbitals of the product is ________.

107.

The correct increasing order of stability of the complex based on $ \Delta_o $ value is:

I. $[\mathrm{Mn}(\mathrm{CN})_6]^{3-}$ II. $[\mathrm{Co}(\mathrm{CN})_6]^{4-}$ III. $[\mathrm{Fe}(\mathrm{CN})_6]^{3-}$ IV. $[\mathrm{Fe}(\mathrm{CN})_6]^{3-}$

108.

The complex cation which has two isomers is:

109.

If $ \mathrm{Ni^{2+}} $ is replaced by $ \mathrm{Pt^{2+}} $ in the complex $ [\mathrm{NiCl_2Br_2}]^{2-} $, which of the following properties are expected to get changed?
I. Geometry
II. Geometrical isomerism
III. Optical isomerism
IV. Magnetic properties

110.

The ratio of spin-only magnetic moment values $ \mu_{\text{eff}}[\text{Cr(CN)}_6]^{3-} / \mu_{\text{eff}}[\text{Cr(H}_2\text{O)}_6]^{3+} $ is ______ .

111.

Given below are two statements:
Statement I: Each electron in $ e_g $ orbitals destabilizes the orbitals by $ +0.6\Delta_o $ and each electron in the $ t_{2g} $ orbitals stabilizes the orbitals by $ -0.4\Delta_o $ in an octahedral field on the basis of crystal field theory.
Statement II: All the $ d $-orbitals of the transition metals have the same energy in their free atomic state but when a complex is formed the ligands destroy the degeneracy of these orbitals on the basis of crystal field theory.
In the light of the above statements, choose the correct answer from the options given below

112.

Match List-I with List-II.

Choose the correct answer from the options given below:

113.

The denticity of an organic ligand, biuret is:

114.

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: The spin only magnetic moment value for $ [\mathrm{Fe}(\mathrm{CN})_6]^{3-} $ is $ 1.74 \, \text{BM} $, whereas for $ [\mathrm{Fe}(\mathrm{H}_2\mathrm{O})_6]^{3+} $ is $ 5.92 \, \text{BM} $.
Reason R: In both complexes, Fe is present in $ +3 $ oxidation state.
In the light of the above statements, choose the correct answer from the options given below:

115.

To inhibit the growth of tumours, identify the compounds used from the following:
A. EDTA B. Coordination compounds of $ \mathrm{Pt} $
C. D-Penicillamine D. Cis-Platin
Choose the correct answer from the options given below:

116.

The number of species from the following that are involved in $ sp^3d^2 $ hybridization is: $ \mathrm{[Co(NH_3)_6]^{3+}} $, $ \mathrm{SF_6} $, $ \mathrm{[CrF_6]^{3-}} $, $ \mathrm{[CoF_6]^{3-}} $, $ \mathrm{[Mn(CN)_6]^{3-}} $ and $ \mathrm{[MnCl_6]^{3-}} $

117.

Which of the following complex is homoleptic?

118.

The number of acyclic structural isomers (including geometrical isomers) for pentene are ______.

119.

Which one of the following metal complexes is most stable?

120.

The number of geometrical isomers found in the metal complexes $ [\mathrm{PtCl_2(NH_3)_2}] $, $ [\mathrm{Ni(CO)_4}] $, $ [\mathrm{Ru(H_2O)_3Cl_3}] $, and $ [\mathrm{CoCl_2(NH_3)_4}]^{+} $ respectively, are:

121.

The metal atom present in the complex $ \mathrm{MABXL} $ (where $ A $, $ B $, $ X $ and $ L $ are unidentate ligands and $ M $ is metal) involves $ \mathrm{sp^3} $ hybridization. The number of geometrical isomers exhibited by the complex is:

122.

Given below are two statements:
Statement (I): Dimethyl glyoxime forms a six-membered covalent chelate when treated with $ \mathrm{NiCl_2} $ solution in presence of $ \mathrm{NH_4OH} $.
Statement (II): Prussian blue precipitate contains ion both in $ (+2) $ and $ (+3) $ oxidation states.
In the light of the above statements, choose the most appropriate answer from the options given below:

123.

Match List-I with List – II:

124.

Given below are two statements:
Statement I: $ \mathrm{PF}_{5} $ and $ \mathrm{BrF}_{5} $ both exhibit $ \mathrm{sp}^{3}\mathrm{d} $ hybridization.
Statement II: Both $ \mathrm{SF}_{6} $ and $ [\mathrm{Co}(\mathrm{NH}_{3})_{6}]^{3+} $ exhibit $ \mathrm{sp}^{3}\mathrm{d}^{2} $ hybridization.
In the light of the above statements, choose the correct answer from the options given below:

125.

Which of the following are true about the energy of the given d-orbital of a tetrahedral complex?
(A) $ d_{xy} = d_{xz} > d_{x^{2}-y^{2}} $
(B) $ d_{xy} = d_{yz} > d_{z^{2}} $
(C) $ d_{x^{2}-y^{2}} > d_{z^{2}} > d_{xz} $
(D) $ d_{x^{2}-y^{2}} = d_{z^{2}} < d_{xz} $
Choose the correct answer from the given below:

126.

The calculated magnetic moments (spin only value) for species $ [\mathrm{FeCl_4}]^{2-} $, $ [\mathrm{Co(C_2O_4)_3}]^{3-} $ and $ \mathrm{MnO_4^{2-}} $ respectively are:

127.

Match List-I with List-II.

Choose the correct answer from the options given below:

128.

Given below are two Statements:
Statement I: Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide.
Statement II: Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc.
In the light of the above statements, choose the most appropriate answer from the options given below:

129.

Spin only magnetic moment in BM of $ [\mathrm{Fe}(\mathrm{CO})_4(\mathrm{C_2O_4})]^+ $ is:

130.

The coordination environment of $ \mathrm{Ca^{2+}} $ ion in its complex with $ \mathrm{EDTA^{4-}} $ is:

131.

Which of the following complex will show largest splitting of $ d $-orbitals?

132.

Chiral complex from the following is: Here en $ = $ ethylene diamine

133.

Indicate the complex/complex ion which did not show any geometrical isomerism:

134.

In the cobalt-carbonyl complex: $ [\mathrm{Co_2(CO)_8}] $, number of Co-co bonds is $ ''X'' $ and terminal CO ligands is $ ''Y'' $. $ X + Y = $ ____________.

135.

Consider a mixture 'X' which is made by dissolving $ 0.4 $ mol of $[\mathrm{Co(NH_3)_5SO_4}]Br$ and $ 0.4 $ mol of $[\mathrm{Co(NH_3)_5Br}]SO_4$ in water to make $ 4 \, \mathrm{L} $ of solution. When $ 2 \, \mathrm{L} $ of mixture 'X' is allowed to react with excess of $ \mathrm{AgNO_3} $, it forms precipitate 'Y'. The rest $ 2 \, \mathrm{L} $ of mixture 'X' reacts with excess $ \mathrm{BaCl_2} $ to form precipitate 'Z'. Which of the following statements is CORRECT?

136.

The correct IUPAC name of $ K_2MnO_4 $ is:

137.

Given below are two statements:

Statement I: The number of paramagnetic species among $ [\mathrm{CoF_6}]^{3-} $, $ [\mathrm{TiF_6}]^{3-} $, $ \mathrm{V_2O_5} $ and $ [\mathrm{Fe(CN)_6}]^{3-} $ is $ 3 $.

Statement II: $ \mathrm{K_4[Fe(CN)_6] < K_3[Fe(CN)_6] < (Fe(H_2O)_6)SO_4 \cdot H_2O < (Fe(H_2O)_6)Cl_3} $ is the correct order in terms of number of unpaired electron(s) present in the complexes.

In the light of the above statements, choose the correct answer from the options given below:

138.

$ 1 \, \mathrm{L},\ 0.02 \, \mathrm{M} $ solution of $ [\mathrm{Co}(\mathrm{NH}_3)_5\mathrm{SO}_4]\mathrm{Br} $ is mixed with $ 1 \, \mathrm{L},\ 0.02 \, \mathrm{M} $ solution of $ [\mathrm{Co}(\mathrm{NH}_3)_5\mathrm{Br}]\mathrm{SO}_4 $. The resulting solution is divided into two equal parts $ (X) $ and treated with excess of $ \mathrm{AgNO}_3 $ solution and $ \mathrm{BaCl}_2 $ solution respectively as shown below :
$ 1 \, \mathrm{L} $ solution $ (X) + \mathrm{AgNO}_3 $ solution (excess) $ \rightarrow Y $
$ 1 \, \mathrm{L} $ solution $ (X) + \mathrm{BaCl}_2 $ solution (excess) $ \rightarrow Z $
The number of moles of $ Y $ and $ Z $ respectively are.

139.

The homoleptic and octahedral complex of $ \text{Co}^{2+} $ and $ \text{H}_2\text{O} $ has __________ unpaired electron(s) in the $ \text{t}_{2g} $ set of orbitals.

140.

‘$ X $’ is the number of electrons in $ t_{2g} $ orbitals of the most stable complex ion among $ [Fe(NH_3)_6]^{3+} $, $ [Fe(Cl)_6]^{3-} $, $ [Fe(C_2O_4)_3]^{3-} $ and $ [Fe(H_2O)_6]^{3+} $. The nature of oxide of vanadium of the type $ V_2O_X $ is:

141.

The correct structures of trans-$ [\mathrm{NiBr_2}(\mathrm{PPh_3})_2] $ and meridional-$ [\mathrm{Co}(\mathrm{NH_3})_3(\mathrm{NO_2})_3] $, respectively, are:

142.

Consider the following pairs of solution which will be isotonic at the same temperature. The number of pairs of solutions is/are $ \_ \_ \_ \_ \_ \_ \_ \_ \_ \_ $.
A. $ 1 \, \text{M} $ aq. $ \mathrm{NaCl} $ and $ 2 \, \text{M} $ aq. Urea
B. $ 1 \, \text{M} $ aq. $ \mathrm{CaCl}_2 $ and $ 1.5 \, \text{M} $ aq. $ \mathrm{KCl} $
C. $ 1.5 \, \text{M} $ aq. $ \mathrm{AlCl}_3 $ and $ 2 \, \text{M} $ aq. $ \mathrm{Na}_2\mathrm{SO}_4 $
D. $ 2.5 \, \text{M} $ aq. $ \mathrm{KCl} $ and $ 1 \, \text{M} $ aq. $ \mathrm{Al}_2(\mathrm{SO}_4)_3 $

143.

Match the LIST-I with LIST-II.

Choose the correct answer from the options given below:

144.

Transition metal complex with highest value of crystal field splitting $ (\Delta_0) $ will be:

145.

Match the List-I wit List-II

List-I Complex ion	List-II Calculated spin only magnetic moment (BM)
A. $ [\mathrm{Cr(H_2O)_6}]^{2+} $	I. $ 3.87 $
B. $ [\mathrm{Co(H_2O)_6}]^{2+} $	II. $ 5.92 $
C. $ [\mathrm{Cu(H_2O)_6}]^{2+} $	III. $ 4.90 $
D. $ [\mathrm{Mn(H_2O)_6}]^{2+} $	IV. $ 1.73 $

Choose the correct answer from the options given below:

146.

In which one of the following metal carbonyls, CO forms a bridge between metal atoms?

147.

$ 1 $ mol of an octahedral metal complex with formula $ \mathrm{MCl_3 \cdot 2L} $ on reaction with excess of $ \mathrm{AgNO_3} $ gives $ 1 $ mol of $ \mathrm{AgCl} $. The denticity of Ligand $ \mathrm{L} $ is __________. (Integer answer)

148.

Amongst $ \mathrm{FeCl_3, \; 3H_2O, \; K_3[Fe(CN)_6]} $ and $ [\mathrm{Co(NH_3)_6}]\mathrm{Cl_3} $, the spin-only magnetic moment value of the inner-orbital complex that absorbs light at shortest wavelength is ___________ B.M. [nearest integer]

149.

Match List I with List II

List I (Complex ion)	List II (Electronic Configuration)
A. $ [\mathrm{Cr(H_2O)_6}]^{3+} $	I. $ t_{2g}{^{2}}e_{g}{^{0}} $
B. $ [\mathrm{Fe(H_2O)_6}]^{3+} $	II. $ t_{2g}{^{3}}e_{g}{^{0}} $
C. $ [\mathrm{Ni(H_2O)_6}]^{2+} $	III. $ t_{2g}{^{3}}e_{g}{^{2}} $
D. $ [\mathrm{V(H_2O)_6}]^{3+} $	IV. $ t_{2g}{^{6}}e_{g}{^{2}} $

Choose the correct answer from the options given below:

150.

The number of optical isomers possible for $ [\mathrm{Cr(C_2O_4)_3}]^{3-} $ is _______.

151.

The sum of bridging carbonyls in $ \mathrm{W(CO)_6} $ and $ \mathrm{Mn_2(CO)_{10}} $ is ________.

152.

A chromium complex with a formula $ \mathrm{CrCl_3\cdot 6H_2O} $ has a spin only magnetic moment value of $ 3.87 \, \text{BM} $ and its solution conductivity corresponds to $ 1:2 $ electrolyte. $ 2.75 \, \text{g} $ of the complex solution was initially passed through a cation exchanger. The solution obtained after the process was reacted with excess of $ \mathrm{AgNO_3} $. The amount of $ \mathrm{AgCl} $ formed in the above process is __________ $ \text{g} $. (Nearest integer)
[Given: Molar mass in $ \text{g mol}^{-1} $ Cr : $ 52 $; Cl : $ 35.5, $ Ag: $ 108 $, O: $ 16 $, H: $ 1 $]

153.

Leaching of gold with dilute aqueous solution of $ \mathrm{NaCN} $ in presence of oxygen gives complex [A], which on reaction with zinc forms the elemental gold and another complex [B]. [A] and [B], respectively are:

154.

Match List-I with List-II :

List-I	List-II
(a) $ [\mathrm{Co(NH_3)_6}][\mathrm{Cr(CN)_6}] $	(i) Linkage isomerism
(b) $ [\mathrm{Co(NH_3)_3}(\mathrm{NO_2})_3] $	(ii) Solvate isomerism
(c) $ [\mathrm{Cr(H_2O)_6}]\mathrm{Cl}_3 $	(iii) Co-ordination isomerism
(d) $ \mathrm{cis}-[\mathrm{CrCl_2(ox)_2}]^{3-} $	(iv) Optical isomerism

Choose the correct answer from the options given below :

155.

According to the valence bond theory the hybridization of central metal atom is $ dsp^2 $ for which one of the following compounds?

156.

The correct order of energy of absorption for the following metal complexes is:
A : $ [\text{Ni}(\text{en})_3]^{2+} $ , B : $ [\text{Ni}(\text{NH}_3)_6]^{2+} $ , C : $ [\text{Ni}(\text{H}_2\text{O})_6]^{2+} $

157.

Choose the correct statements from the following:
(A) Ethane-$ 1, 2 $-diamine is a chelating ligand.
(B) Metallic aluminium is produced by electrolysis of aluminium oxide in presence of cryolite.
(C) Cyanide ion is used as ligand for leaching of silver.
(D) Phosphine act as a ligand in Wilkinson catalyst.
(E) The stability constants of $ \mathrm{Ca^{2+}} $ and $ \mathrm{Mg^{2+}} $ are similar with EDTA complexes.
Choose the correct answer from the options given below:

158.

The mismatch combinations are:
A. Chlorophyll–Co B. Water hardness – EDTA C. Photography – $ [\text{Ag}(\text{CN})_{2}]^{-} $ D. Wilkinson catalyst – $ [(\text{Ph}_{3}\text{P})_{3}\text{RhCl}] $ E. Chelating ligand – D-Penicillamine
Choose the correct answer from the options given below:

159.

The complex of $ \text{Ni}^{2+} $ ion and dimethyl glyoxime contains __________ number of Hydrogen $ (\text{H}) $ atoms.

160.

Total number of relatively more stable isomer(s) possible for octahedral complex $ [\mathrm{Cu(en)_2(SCN)_2}] $ will be ____________.

161.

$ [\mathrm{Fe}(\mathrm{CN})_6]^{3-} $ should be an inner orbital complex. Ignoring the pairing energy, the value of crystal field stabilization energy for this complex is $ (-) $ __________ $ \Delta_0 $. (Nearest integer)

162.

The correct order of the number of unpaired electrons in the given complexes is:
(A) $ [\mathrm{Fe}(\mathrm{CN})_6]^{3-} $ (B) $ [\mathrm{FeF}_6]^{3-} $
(C) $ [\mathrm{CoF}_6]^{3-} $ (D) $ [\mathrm{Cr}(\text{oxalate})_3]^{3-} $
(E) $ [\mathrm{Ni}(\mathrm{CO})_4] $
Choose the correct answer from the options given below:

163.

White precipitate of $ \mathrm{AgCl} $ dissolves in aqueous ammonia solution due to formation of :

164.

Given below are two statements:
Statement I: Among $ \mathrm{Zn}, \mathrm{Mn}, \mathrm{Sc} $ and $ \mathrm{Cu} $, the energy required to remove the third valence electron is highest for $ \mathrm{Zn} $ and lowest for $ \mathrm{Sc} $.
Statement II: The correct order of the following complexes in terms of CFSE is $ [\mathrm{Co}(\mathrm{H_2O})_6]^{2+} < [\mathrm{Co}(\mathrm{H_2O})_6]^{3+} < [\mathrm{Co}(\mathrm{en})_3]^{3+} $.
In the light of the above statements, choose the correct answer from the options given below:

165.

The spin-only magnetic moment value for the complex $ [\mathrm{Co(CN)_6}]^{4-} $ is ________ BM. [At. no. of Co $ = 27 $]

166.

The correct order of $ [\mathrm{FeF_6}]^{3-} $, $ [\mathrm{CoF_6}]^{3-} $, $ [\mathrm{Ni(CO)_4} ]$ and $ [\mathrm{Ni(CN)_4}]^{2-} $ complex species based on the number of unpaired electrons present is:

167.

Total number of moles of $ \mathrm{AgCl} $ precipitated on addition of excess of $ \mathrm{AgNO_3} $ to one mole each of the following complexes $ [\mathrm{Co(NH_3)_4Cl_2}]\mathrm{Cl} $, $ [\mathrm{Ni(H_2O)_6}]\mathrm{Cl_2} $, $ [\mathrm{Pt(NH_3)_2Cl_2}] $ and $ [\mathrm{Pd(NH_3)_4}]\mathrm{Cl_2} $ is _______.

168.

Match List - I with List - II.

Choose the correct answer from the options given below:

169.

Arrange the following coordination compounds in the increasing order of magnetic moments. (Atomic numbers: $ \mathrm{Mn} = 25 $; $ \mathrm{Fe} = 26 $)
A. $ [\mathrm{FeF}_{6}]^{3-} $
B. $ [\mathrm{Fe(CN)}_{6}]^{3-} $
C. $ [\mathrm{MnCl}_{6}]^{3-} $ (high spin)
D. $ [\mathrm{Mn(CN)}_{6}]^{3-} $
Choose the correct answer from the options given below:

170.

The secondary valency and number of hydrogen bonded water molecules in $ \mathrm{CuSO_4 \cdot 5H_2O} $, respectively, are:

171.

One mole of the octahedral complex compound $ \mathrm{Co(NH_3)_5 Cl_3} $ give $ 3 $ moles of ions on dissolution in water. One mole of the same complex reacts with excess of $ \mathrm{AgNO_3} $ solution to yield two moles of $ \mathrm{AgCl(s)} $. The structure of the complex is:

172.

Which of the following is correct order of ligand field strength?

173.

The sum of oxidation states of two silver ions in $[\mathrm{Ag}(\mathrm{NH}_3)_2][\mathrm{Ag}(\mathrm{CN})_2]$ complex is:

174.

An octahedral complex having molecular composition $ \mathrm{Co.5NH3.Cl.SO4} $ has two isomers A and B. The solution of A gives a white precipitate with $ \mathrm{AgNO3} $ solution and the solution of B gives white precipitate with $ \mathrm{BaCl2} $ solution. The type of isomerism exhibited by the complex is:

175.

The correct order of spin only magnetic moments for the following complex ions is:

176.

Number of paramagnetic complexes among the following is ______:
$ \left[\mathrm{MnBr_4}\right]^{2-},\ \left[\mathrm{NiCl_4}\right]^{2-},\ \left[\mathrm{Ni(CN)_4}\right]^{2-},\ \left[\mathrm{Ni(CO)_4}\right],\ \left[\mathrm{CoF_6}\right]^{3-},\ \left[\mathrm{Fe(CN)_6}\right]^{4-},\ \left[\mathrm{Mn(CN)_6}\right]^{3-},\ \left[\mathrm{Ti(CN)_6}\right]^{3-},\ \left[\mathrm{Cu(H_2O)_6}\right]^{2+},\ \left[\mathrm{Co(C_2O_4)_3}\right]^{3-} $

177.

Octahedral complexes of copper $ (\mathrm{II}) $ undergo structural distortion (Jahn-Teller). Which one of the given copper $ (\mathrm{II}) $ complexes will show the maximum structural distortion? (en – ethylenediamine; $ \mathrm{H_2N - CH_2 - CH_2 - NH_2} $ )

178.

The total number of unpaired electrons present in the complex $ \mathrm{K_3[Cr(oxalate)_3]} $ is __________.

179.

The d-electronic configuration of $ [\text{CoCl}_4]^{2-} $ in tetrahedral crystal field is $ e^{m} t_{2}^{n} $. Sum of “m” and “n” _________.

180.

In potassium ferrocyanide, there are ______ pairs of electrons in the $ t_{2g} $ set of orbitals.

181.

The correct order of intensity of colors of the compounds is:

182.

Match List I with List II.

Choose the correct answer from the options given below:

183.

Identify the coordination complexes in which the central metal ion has $ d^4 $ configuration.
(A) $ \mathrm{[FeO_4]^{2-}} $
(B) $ \mathrm{[Mn(CN)_6]^{3-}} $
(C) $ \mathrm{[Fe(CN)_6]^{3-}} $
(D) $ \text{Cr}_2(\text{O}-\overset{\overset{\text{O}}{\parallel}}{\text{C}}-\text{Me})_4(\text{H}_2\text{O})_2$
(E) $ \mathrm{[NiF_6]^{2-}} $

Choose the correct answer from the options given below:

184.

Which of the following complexes will show coordination isomerism?

A. $ [\mathrm{Ag}(\mathrm{NH}_3)_2][\mathrm{Ag}(\mathrm{CN})_2] $

B. $ [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Cr}(\mathrm{CN})_6] $

C. $ [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Co}(\mathrm{CN})_6] $

D. $ [\mathrm{Fe}(\mathrm{NH}_3)_6][\mathrm{Co}(\mathrm{CN})_6] $

E. $ [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Fe}(\mathrm{CN})_6] $

Choose the correct answer from the options given below:

185.

Which one of the following complexes will exhibit the least paramagnetic behaviour? $[ \text{Atomic number, Cr} = 24, \text{ Mn} = 25, \text{ Fe} = 26, \text{ Co} = 27 ]$

186.

The hybridization and magnetic behaviour of cobalt ion in $ [\mathrm{Co}(\mathrm{NH}_3)_6]^{3+} $ complex, respectively is:

187.

Identify the CORRECT set of details from the following:
A. $ [\mathrm{Co}(\mathrm{NH}_3)_6]^{3+} $: Inner orbital complex; $ d^{2}sp^{3} $ hybridized
B. $ \mathrm[{MnCl}_6]^{3-} $: Outer orbital complex; $ sp^{3}d^{2} $ hybridized
C. $ [\mathrm{CoF}_6]^{3-} $: Outer orbital complex; $ d^{2}sp^{3} $ hybridized
D. $ [\mathrm{FeF}_6]^{3-} $: Outer orbital complex; $ sp^{3}d^{2} $ hybridized
E. $ [\mathrm{Ni}(\mathrm{CN})_4]^{2-} $: Inner orbital complex; $ sp^{3} $ hybridized
Choose the correct answer from the options given below:

188.

The correct sequence of ligands in the order of decreasing field strength is:

189.

Number of stereoisomers possible for the complexes, $ [\text{CrCl}_3(\text{py})_3] $ and $ [\text{CrCl}_2(\text{ox})_2]^{3-} $ are respectively (py = pyridine, ox = oxalate)

190.

Match the List-I with List-II.

List-I Electronic configuration of tetrahedral metal ion	List-II Crystal Field Stabilization Energy ($ \Delta_t $)
A. $ d^{2} $	I. $ -0.6 $
B. $ d^{4} $	II. $ -0.8 $
C. $ d^{6} $	III. $ -1.2 $
D. $ d^{8} $	IV. $ -0.4 $

Choose the correct answer from the options given below:

191.

Total number of molecules/species from following which will be paramagnetic is ____________.
$[ \mathrm{O_2}, \ \mathrm{O_2^{+}}, \ \mathrm{O_2^{-}}, \ \mathrm{NO}, \ \mathrm{NO_2}, \ \mathrm{CO}, \ \mathrm{K_2[NiCl_4]}, \ [\mathrm{Co(NH_3)_6}]\mathrm{Cl_3}, \ \mathrm{K_2[Ni(CN)_4]} $

192.

Select the option with correct property:

193.

Total number of unpaired elecrons in the complex ions $ [\mathrm{Co(NH_3)_6}]^{3+} $ and $ [\mathrm{NiCl_4}]^{2-} $ is:

194.

The correct order of the following complexes in term of their crystal field stabilization energies is:

195.

Given below are two statements:
Statement (I) : The octahedral complexes, when $ \Delta_o < P $ high spin complex are formed. When $ \Delta_o > P $ low spin complexes are formed.
Statement (II) : In tetrahedral complexes because of $ \Delta_t < P $, low spin complex are rarely formed.
In the light of the above statements, choose the most appropriate answer from the options given below:

196.

Consider the following complex ions
$ P = [\text{FeF}_6]^{3-} $
$ Q = [\text{V}(\text{H}_2\text{O})_6]^{2+} $
$ R = [\text{Fe}(\text{H}_2\text{O})_6]^{2+} $
The correct order of the complex ions, according to their spin only magnetic moment values (in $ \text{B.M.} $), is:

197.

The type of hybridization and the magnetic property of $ [\mathrm{MnCl_6}]^{3-} $ are,

198.

$[\mathrm{Ti}(\mathrm{H}_2\mathrm{O})_6]^{3+} $ absorbs light of wavelength $ 498 \, \text{nm} $ during a d – d transition. The octahedral splitting energy for the above complex is __________ $ \times 10^{-19} \, \text{J} $. (Round off to the Nearest Integer). $ h = 6.626 \times 10^{-34} \, \text{Js}; \, c = 3 \times 10^{8} \, \text{m s}^{-1} $.

199.

For the reaction given below:
$ \text{CoCl}_3 \cdot x \text{NH}_3 + \text{AgNO}_3 \, (\text{aq}) \rightarrow $
If $ 2 $ equivalents of $ \text{AgCl} $ precipitate out, then the value of $ x $ will be ______.

200.

If $ [\mathrm{Cu(H_2O)_4}]^{2+} $ absorbs a light of wavelength $ 600 \, \text{nm} $ for d-d transition, then the value of octahedral crystal field splitting energy for $ [\mathrm{Cu(H_2O)_6}]^{2+} $ will be __________ $ \times 10^{-21} \, \text{J} $. (Nearest Integer)
[Given : $ h = 6.63 \times 10^{-34} \, \text{J s} $ and $ c = 3.08 \times 10^{8} \, \text{m s}^{-1} $ ]

201.

The correct order of ligands arranged in increasing field strength.

202.

Number of complexes which will exhibit synergic bonding amongst, $ [\mathrm{Cr}(\mathrm{CO})_6] $, $ [\mathrm{Mn}(\mathrm{CO})_5] $ and $ [\mathrm{Mn}_2(\mathrm{CO})_{10}] $ is ______.

203.

The number of paramagnetic species from the following is ____________ .
$ [\mathrm{Ni(CN)_4}]^{2-},\ [\mathrm{Ni(CO)_4}],\ [\mathrm{NiCl_4}]^{2-},\ [\mathrm{Fe(CN)_6}]^{4-},\ [\mathrm{Cu(NH_3)_4}]^{2+},\ [\mathrm{Fe(CN)_6}]^{3-} $ and $ [\mathrm{Fe(H_2O)_6}]^{2+} $

204.

Given below are two statements:

Statement I : Among $ \left[\mathrm{Cu(NH_3)_4}\right]^{2+} $, $ \left[\mathrm{Ni(en)_3}\right]^{2+} $, $ \left[\mathrm{Ni(NH_3)_6}\right]^{2+} $ and $ \left[\mathrm{Mn(H_2O)_6}\right]^{2+} $,$ \left[\mathrm{Mn(H_2O)_6}\right]^{2+} $ has the maximum number of unpaired electrons.

Statement II : The number of pairs among $ \left\{ \left[\mathrm{NiCl_4}\right]^{2-}, \left[\mathrm{Ni(CO)_4}\right] \right\} $, $ \left\{ \left[\mathrm{NiCl_4}\right]^{2-}, \left[\mathrm{Ni(CN)_4}\right]^{2-} \right\} $ and $ \left\{ \left[\mathrm{Ni(CO)_4}\right], \left[\mathrm{Ni(CN)_4}\right]^{2-} \right\} $ that contain only diamagnetic species is two.

In the light of the above statements, choose the correct answer from the options given below:

205.

The spin-only magnetic moment value of an octahedral complex among $ \mathrm{CoCl_3 \cdot 4NH_3} $, $ \mathrm{NiCl_2 \cdot 6H_2O} $ and $ \mathrm{PtCl_4 \cdot 2HCl} $, which upon reaction with excess of $ \mathrm{AgNO_3} $ gives $ 2 $ moles of $ \mathrm{AgCl} $ is ___________ B.M. (Nearest Integer)

← PreviousQuestion 51 of 205Next →

JEE Main 2026 4th April Evening Shift

JEE MainsJEE AdvanceBITSATJEE Mains | PYQ

JEE Mains JEE Advance BITSAT
JEE Mains | PYQ