Coordination Compounds PYQs Set 1 (PDF)

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Mere Teacher · Previous Year Questions JEE Main Chemistry · Coordination Compounds · Set 1 (Q1-30)
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1. $Select the option with correct property -$ (1) $(Ni (CO)_{4}) and (NiCl_{4})^{2 -} both diamagnetic$ (2) $(Ni (CO)_{4}) and (NiCl_{4})^{2 -} both paramagnetic$ (3) $(NiCl_{4})^{2 -} diamagnetic, (Ni (CO)_{4}) paramagnetic$ (4) $(Ni (CO)_{4}) diamagnetic, (NiCl_{4})^{2 -} paramagnetic$ 2. $Which of the following name formula combinations is not correct ? Formula Name$ (1) $K_{2} [Pt (C N)_{4}] Potasium tetracyanoplatinate (II)$ (2) $[Mn(CN)_{5}]^{2-} Pentacyanomagnate (II) ion$ (3) $K[Cr(N H_{3})_{2} C l_{4}] Potassium diammine tetrachlorochromate (III)$ (4) $[Co (N H_{3})_{4} (H_{2} O)l] S O_{4} Tetraammine aquaiodo cobalt (III) sulphate$ 3. $Identify the formula of bis (ethylenediamine) dithiocyanatoplatinum(IV).$ (1) $Pt ((en)_{2} S_{2} CN)^{4 -}$ (2) $Pt ((en)_{2} S_{2} CN)^{4 +}$ (3) $(Pt (en) (SCN)_{2})^{4 -}$ (4) $(Pt (en)_{2} (SCN)_{2})^{2 +}$ 4. $CrCl_{3} \cdot xNH_{3} can exist as a complex. 0.1 molal aqueous solution of this complex shows a depression in freezing point of 0.558^{\circ} C . Assuming 100 % ionisation of this complex and coordination number of Cr is 6 , the complex will be (Given K_{f} = 1.86 K kg mol^{- 1})$ (1) $(Cr (NH_{3})_{5} Cl) Cl_{2}$ (2) $(Cr (NH_{3})_{6}) Cl_{3}$ (3) $(Cr (NH_{3})_{3} Cl_{3})$ (4) $(Cr (NH_{3})_{4} Cl_{2}) Cl$ 5. $Consider the coordination compound, [Co (N H_{3})_{6}] C l_{3} . In the formation of the complex, the species which acts as the Lewis acid is$ (1) $[Co(N H_{3})_{6}]^{3 +}$ (2) $C l^{-}$ (3) $C o^{3 +}$ (4) $N H_{3}$ 6. $A complex compound in which the oxidation number of a metal is zero$ (1) $(Ni (CO)_{4})$ (2) $(Pt (NH_{3})_{4}) Cl_{2}$ (3) $K_{4} (Fe (CN)_{6})$ (4) $K_{3} (Fe (CN)_{6})$ 7. $The magnetic moment of an octahedral homoleptic Mn (II) complex is 5.9 BM . The suitable ligand for this complex is:$ (1) $Ethylenediamine$ (2) $CN^{-}$ (3) $NC S^{-}$ (4) $CO$ 8. $Which of the following statement is false ?$ (1) $Mg2+ ions are important in the green parts of plants.$ (2) $Mg2+ ions from a complex with ATP.$ (3) $Ca2+ ions are important in blood clotting.$ (4) $Ca2+ ions are not important in maintaining the regular beating of the heart.$ 9. $The species that has a spin-only magnetic moment of 5.9 BM, is T_{d} = tetrahedral)$ (1) $[MnBr_{4}]^{2 -} (T_{d})$ (2) $[NiCl_{4}]^{2 -} (T_{d})$ (3) $Ni (CO)_{4} (T_{d})$ (4) $[Ni (CN)_{4}]^{2 -} (square planar)$ 10. $Which one of the following complexes is violet in colour?$ (1) $[Fe(CN)_{6}]^{4 -}$ (2) $[Fe(SCN)_{6}]^{4 -}$ (3) $F e_{4} [F e (C N_{6})]_{3} \cdot H_{2} O$ (4) $(Fe (CN)_{5} NOS)^{4 -}$ 11. $Nickel (Z = 28) combines with a uninegative monodenate ligand to form a diamagnetic complex [N i L_{4}]^{2-} . The hybridisation involved and the number of unpaired electrons present in the complex are respectively:$ (1) $s p^{3}, two$ (2) $d s p^{2}, zero$ (3) $d s p^{2}, one$ (4) $s p^{3}, zero$ 12. $In which one of the pairs of ion given, there is an ion that forms a coordination compound with both aqueous sodium hydroxide and ammonia and an other ion that forms a coordination compound only with aqueous sodium hydroxide?$ (1) $Pb^{2 +}, Cu^{2 +}$ (2) $Zn^{2 +}, Al^{3 +}$ (3) $Cu^{2 +}, Zn^{2 +}$ (4) $Al^{3 +}, Cu^{2 +}$ 13. $Homoleptic octahedral complexes of a metal ion M^{3 +} with three monodentate ligands L_{1}, L_{2} and L_{3} absorb wavelengths in the region of green, blue and red respectively. The increasing order of the ligand strength is:$ (1) $L_{3} < L_{1} < L_{2}$ (2) $L_{3} < L_{2} < L_{1}$ (3) $L_{1} < L_{2} < L_{3}$ (4) $L_{2} < L_{1} < L_{3}$ 14. $Which one of the following complexes will consume more equivalents of aqueous solution of Ag(N O_{3}) ?$ (1) $N a_{3} [C r C l_{6}]$ (2) $[Cr (H_{2} O)_{5} Cl] C l_{2}$ (3) $[Cr (H_{2} O)_{6}] C l_{3}$ (4) $N a_{2} [C r C l_{5} (H_{2} O)]$ 15. $Which one of the following complexes is not expected to exhibit isomerism?$ (1) $[N i (N H_{3})_{4} (H_{2} O)_{2}]^{2 +}$ (2) $[P t (N H_{3})_{2} C l_{2}]$ (3) $[N i (N H_{3})_{2} C l_{2}]$ (4) $[N i (e n)_{3}]^{2 +}$ 16. $How many ions per molecule are produced in the solution when Mohr salt is dissolved in excess of water?$ (1) $5$ (2) $10$ (3) $4$ (4) $6$ 17. $Consider the transition metal ions Mn^{3 +}, Cr^{3 +}, Fe^{3 +} and Co^{3 +} and all form low spin octahedral complexes. The correct decreasing order of unpaired electrons in their respective d-orbitals of the complexes is$ (1) $Mn^{3 +} > Fe^{3 +} > Co^{3 +} > Cr^{3 +}$ (2) $Cr^{3 +} > Mn^{3 +} > Fe^{3 +} > Co^{3 +}$ (3) $Fe^{3 +} > Co^{3 +} > Mn^{3 +} > Cr^{3 +}$ (4) $Cr^{3 +} > Fe^{3 +} > Co^{3 +} > Mn^{3 +}$ 18. $Three complexes,[CoCl(N H_{3})_{5}]^{2 +} (I), [Co(N H_{3})_{5} H_{2} O]^{3 +} (II) and [Co(N H_{3})_{6}]^{3 +} (III) absorb light in the visible region. The correct order of the wavelength of light absorbed by them is :$ (1) $(III) > (I) > (II)$ (2) $(II) > (I) > (III)$ (3) $(I) > (II) > (III)$ (4) $(III) > (II) > (I)$ 19. $Which of the following complexes has lowest molar conductance?$ (1) $CoCl_{3} \cdot 3 NH_{3}$ (2) $CoCl_{3} \cdot 4 NH_{3}$ (3) $CoCl_{3} \cdot 5 NH_{3}$ (4) $CoCl_{3} \cdot 6 NH_{3}$ 20. $Two complexes [C r (H_{2} O)_{6}] C l_{3} (a) and [C r (N H_{3})_{6}] C l_{3} (b) are violet and yellow coloured respectively. The incorrect statement regarding them is :$ (1) $Δ0 value for (a) is less than that of (b).$ (2) $both absorb energies corresponding to their complementary colors.$ (3) $Δ0 values of (a) and (b) are calculated from the energies of violet and yellow light, respectively.$ (4) $both are paramagnetic with three unpaired electrons.$ 21. $One mole of the octahedral complex compound Co (NH_{3})_{5} Cl_{3} gives 3 moles of ions on dissolution in water. One mole of the same complex reacts with excess of AgNO_{3} solution to yield two moles of AgCl_{(s)} . The structure of the complex is:$ (1) $(Co (NH_{3})_{4} Cl_{2}) \cdot Cl \cdot NH_{3}$ (2) $(Co (NH_{3})_{3} Cl_{3}) \cdot 2 NH_{3}$ (3) $(Co (NH_{3})_{5} Cl) Cl_{2}$ (4) $(Co (NH_{3})_{4} Cl) \cdot Cl_{2} \cdot NH_{3}$ 22. $The IUPAC name of the complex [Pt (N H_{3})_{2} Cl(N H_{2} C H_{3})]Cl is :$ (1) $Bisammine(methanamine)chloridoplatinum(II)chloride$ (2) $Diammine(methanamine)chloridoplatinum(II)chloride.$ (3) $Diamminechlorido(methanamine)platinum(II)chloride$ (4) $Diamminechlorido(amminomethane)platinum(II)chloride$ 23. $Atomic number of Cr and Fe are respectively 24 and 26, which of the following is paramagnetic with the spin of electron?.$ (1) $[C r (C O)_{6}]$ (2) $[F e (C O)_{5}]$ (3) $[F e (C N)_{6}]^{4 -}$ (4) $[C r (N H_{3})_{6}]^{3 +}$ 24. $The complex hexamineplatinum(IV) chloride will give ionisation.$ (1) $3$ (2) $2$ (3) $5$ (4) $4$ 25. $The number of unidentate ligands in the complex ion is called$ (1) $oxidation number$ (2) $primary valency$ (3) $coordination number$ (4) $EAN.$ 26. $Which one of the following has a square planar geometry? (At. no. Co = 27, Ni = 28, Fe = 26, Pt = 78)$ (1) $[N i C l_{4}]^{2-}$ (2) $[P tC l_{4}]^{2-}$ (3) $[C o C l_{4}]^{2-}$ (4) $[F e C l_{4}]^{2-}$ 27. $Reaction of [Co(H_{2} O)_{6}]^{2 +} with excess ammonia and in the presence of oxygen results into a diamagnetic product. Number of electrons present in t_{2 g} -orbitals of the product is_______.$ 28. $The total number of unpaired electrons present in the complex K_{3} (Cr (oxalate)_{3}) is____.$ 29. $Dichromate ion is treated with base, the oxidation number of Cr in the product formed is:$ 30. $The volume (in mL) of 0.1 M A g N O_{3} required for complete precipitation of chloride ions present in 30 mL of 0.01 M solution of [Cr (H_{2} O)_{5} Cl] C l_{2}, as silver chloride is close to.$