CBSE Class 12 Chemistry Coordination Compounds MCQs Set 06

Question. IUPAC name of Na₃[Co(ONO)₆] is
(a) Sodium cobaltinitrite
(b) Sodium hexanitrito cobaltate (III)
(c) Sodium hexanitrocobalt (III)
(d) Sodium hexanitritocobaltate (II)
Answer: b

Question. Which of the following statements is correct ? (Atomic number of Ni = 28)
(a) Ni(CO)₄ is diamagnetic and [NiCl₄]^2– and [Ni(CN)₄]^2– are paramagnetic
(b) Ni(CO)₄ and [Ni(CN)₄]^2– are diamagnetic and [NiCl4]^2– is paramagnetic
(c) Ni(CO)₄ and [NiCl₄]^2–are diamagnetic and [Ni(CN)₄]^2– is paramagnetic
(d) [NiCl₄]^2– and [Ni(CN)₄]^2– are diamagnetic and Ni(CO)₄ is paramagnetic
Answer: b

Question. Which of the following species represent the example of dsp² – hybridisation ?
(a) [Fe(CN)₆]^3–
(b) [Ni(CN)₄]^2–
(c) [Ag(CN)₂]^–
(d) [Co(CN)₆]^3–
Answer: b

Question. A coordination compound CrCl₃⋅4H₂O gives white precipitate of AgCl with AgNO₃. The molar conductance of the compound corresponds to two ions. The structural formula of the compound is
(a) [Cr(H₂O)₄Cl₃]
(b) [Cr(H₂O)₃Cl₃]H₂O
(c) [Cr(H₂O)₄Cl₂]Cl
(d) [Cr(H₂O)₄Cl]Cl₂
Answer: c

Question. Which of the following will give maximum number of isomers?
(a) [Co(NH₃)₄Cl₂]
(b) [Ni(en)(NH₃)₄]²⁺
(c) [Ni(C₂O₄)(en)₂]
(d) [Cr(SCN)₂(NH₃)₄]²⁺
Answer: d

Question. Low spin tetrahedral complexes are not formed because
(a) for tetrahedral complexes, the CFSE is lower than pairing energy
(b) for tetrahedral complexes, the CFSE is higher than pairing energy
(c) electrons do not go to eg in case of tetrahedral complexes
(d) tetrahedral complexes are formed by weak field ligands only.
Answer: a

Question. Which of the following compounds shows optical isomerism?
(a) [Co(CN)₆ ] ^3-
(b) [Cr(C₂O₄ )₃ ]^3-
(c) [ZnCl₄ ]^2-
(d) [Cu(NH₃ )₄ ]²⁺
Answer: b

Question. Which has maximum paramagnetic nature ?
(a) [Mn(H₂O)₆ ]²⁺
(b) [Cu(NH₃)₄ ]²⁺
(c) [Fe(CN)₆ ]^4-
(d) [Cu(H₂O)₄ ]²⁺
Answer: a

Question. Which of the following does not depict the correct name of the compound?
(a) K₂[Zn(OH)₄] : Potassium tetrahydroxozincate(II)
(b) [Co(NH₃)₅CO₃]Cl : Pentaammine carbonatochlorocobaltate(III)
(c) Na₃[Co(NO₂)₆] : Sodium hexanitrocobaltate(III)
(d) K₃[Cr(CN)₆] : Potassium hexacyanochromate(III)
Answer: b

Question. Which of the following does not show optical isomerism?
(a) [Co(NH₃)₃Cl₃]⁰
(b) [Co (en) Cl₂ (NH₃)₂]⁺
(c) [Co (en)₃]³⁺
(d) [Co (en)₂Cl₂]⁺ (en = ethylenediamine) 
Answer: a

Question. Which of the following is the correct name of compound.
[Co(NH₃)₄(H₂O)Cl]Cl₂
(a) Tetraamineaqua chloride cobalt (III) chloride
(b) Tetraamineaqua chlorido cobalt (II) chloride
(c) Tetraamineaqua chloride cobalt (II) chloride
(d) Tetraamineaqua chlorido cobalt (III) chloride
Answer: d

Question. The number of unpaired electrons in the complex [Cr(NH₃)₆]Br₃ is (Atomic number Cr = 24)
(a) 4
(b) 1
(c) 2
(d) 3
Answer: d

 Question. Which of the following is not correctly matched?
(a) Coordination compound containing cationic complex ion : [Fe(H₂O)₂(C₂O₄)₂]₂SO₄
(b) Coordination compound containing anionic complex ion : [Ag(NH₃)₂]Cl
(c) Non-ionic coordination compound : [Co(NO₂)₃(NH₃)₃]
(d) Coordination compound containing cationic and anionic complex ion : [Pt(NH₃)₄] [CuCl₄]
Answer: b

Question. Which of the following descriptions about [FeCl₆]^4– is correct about the complex ion?
(a) sp³d, inner orbital complex, diamagnetic
(b) sp³d², outer orbital complex, paramagnetic
(c) d²sp³, inner orbital complex, paramagnetic
(d) d²sp³, outer orbital complex, diamagnetic
Answer: b

Question. Which one of the following cyano complexes would exhibit the lowest value of paramagnetic behaviour ?
(a) [Co(CN)₆ ]^3-
(b) [Fe(CN)₆ ]^3-
(c) [Mn(CN)₆ ]^3-
(d) [Cr(CN)₆ ]^3-
(At. Nos : Cr = 24, Mn = 25, Fe = 26, Co = 27)
Answer: a

Question. Change in composition of co-ordination sphere yields which type of isomers
(a) optical
(b) geometrical
(c) ionisation
(d) None of these
Answer: c

Question. Ammonia acts as a very good ligand but ammonium ion does not form complexes because
(a) NH₃ is a gas while NH₄⁺ is in liquid form
(b) NH₃ undergoes sp³ hybridisation while NH₄⁺ undergoes sp³d hybridisation
(c) NH₄⁺ ion does not have any lone pair of electrons
(d) NH₄⁺ ion has one unpaired electron while NH₃ has two unpaired electrons.
Answer: c

 Question. Which of the following will exhibit optical isomerism ?
(a) [Cr(en) (H₂O)₄]3+
(b) [Cr(en)₃]³⁺
(c) trans-[Cr(en)(Cl₂)(NH₃)₂]⁺
(d) [Cr(NH₃)₆]³⁺
Answer: b

Question. Which of the following has a square planar geometry?
(a) [PtCl₄]^2–
(b) [CoCl₄]^2–
(c) [FeCl₄]^2–
(d) [NiCl₄]^2–
(At. nos.: Fe = 26, Co = 27, Ni = 28, Pt = 78)
Answer: a

Question. The type of isomerism present in nitropentaamminechromium (III) chloride is
(a) optical
(b) linkage
(c) ionization
(d) polymerization
Answer: b

Question. Coordination isomerism is caused by the interchange of ligands between the
(a) cis and trans structure
(b) complex cation and complex anion
(c) inner sphere and outer sphere
(d) low oxidation and higher oxidation states
Answer: b

Question. A coordination compound X gives pale yellow colour with AgNO₃ solution while its isomer Y gives white precipitate with BaCl₂. Two compounds are isomers of CoBrSO₄⋅5NH₃. What could be the possible formula of X and Y?
(a) X = [Co(NH₃)₅SO₄]Br, Y = [Co(NH₃)₅Br]SO₄
(b) X = [Co(NH₃)₅Br]SO₄, Y = [Co(NH₃)₅SO₄]Br
(c) X = [Co(NH₃)₅Br(SO₄)], Y = [CoBr(SO₄)(NH₃)₅]
(d) X = [Co(Br)₅NH₃]SO₄, Y = [CoBr(SO₄)]NH₃
Answer: a

Question. The ionisation isomer of [Cr(H₂O)₄Cl(NO₂)]Cl is
(a) [Cr(H₂O)₄(O₂N)]Cl₂
(b) [Cr(H₂O)₄Cl₂](NO₂)
(c) [Cr(H₂O)₄Cl(ONO)]Cl
(d) [Cr(H₂O)₄Cl₂(NO₂)].H₂O
Answer: b

Question. Which one of the following has an optical isomer?
(a) [Zn(en) (NH₃)₂]²⁺
(b) [Co(en)₃]³⁺
(c) [Co(H₂O)₄(en)]³⁺
(d) [Zn(en)₂]²⁺
(en = ethylenediamine)
Answer: b