CBSE Class 12 Chemistry Coordination Compounds MCQs Set G

Question. Which one of the following complex ions has geometrical isomers ?
(a) [Ni(NH₃)₅Br]⁺
(b) [Co(NH₃)₂(en)₂]³⁺
(c) [Cr(NH₃)₄(en)₂]³⁺
(d) [Co(en)₃]³⁺
(en = ethylenediamine)
Answer: b

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

Question. Which of the following coordination compounds would exhibit optical isomerism?
(a) pentamminenitrocobalt(III) iodide
(b) diamminedichloroplatinum(II)
(c) trans-dicyanobis (ethylenediamine) chromium (III) chloride
(d) tris-(ethylendiamine) cobalt (III) bromide
Answer: d

Question. The geometry of Ni(CO)₄ and Ni(PPh₃)₂Cl₂ are
(a) both square planar
(b) tetrahedral and square planar
(c) both tetrahedral
(d) None of these
Answer: c

Question. The type of isomerism present in Pentaminenitrochromium (III) chloride is
(a) optical
(b) linkage
(c) ionisation
(d) polymerisation.
Answer: b

Question. Which of the following type of isomerism is shown by given complex compound?
(a) Facial
(b) Meridional
(c) Cis
(d) Both b and c
Answer: b

Question. Which of the following ions can exhibit optical isomerism–
(a) [Co(NH₃)₄Cl₂]⁺
(b) [Co(NH₃)₂Cl₄]^–
(c) Cis-[Co(en)₂Cl₂]⁺
(d) trans-[Co(en)₂Cl₂]⁺
Answer: c

Question. Which would exhibit co-ordination isomerism
(a) [Cr(NH₃)₆][Co(CN)₆]
(b) [Co(en)₂Cl₂]
(c) [Cr(NH₃)₆]Cl₃
(d) [Cr(en)₂Cl₂]⁺
Answer: a

Question. [Co(NH₃)₅NO₂]Cl₂ and [Co(NH₃)₅(ONO)]Cl₂ are related to each other as
(a) geometrical isomers
(b) optical isomers
(c) linkage isomers
(d) coordination isomers 
Answer: c

Question. The complexes [Co(NH₃)₆] [Cr(CN)₆] and [Cr(NH₃)₆]
[Co(CN)₆] are the examples of which type of isomerism?
(a) Linkage isomerism
(b) Ionization isomerism
(c) Coordination isomerism
(d) Geometrical isomerism
Answer: c

Question. The complex, [Pt(py)(NH₃)BrCl] will have how many geometrical isomers ?
(a) 3
(b) 4
(c) 0
(d) 2
Answer: a

Question. Which one of the following will show paramagnetism corresponding to 2 unpaired electrons?
(Atomic numbers : Ni = 28, Fe = 26)
(a) [FeF₆]^3–
(b) [NiCl₄]^2–
(c) [Fe(CN)₆]^3–
(d) [Ni(CN)₄]^2–
Answer: b

Question. Isomerism exhibited by [Cr(NH₃)₂(H₂O)₂Cl₂]⁺ are –
(a) ionization, optical
(b) hydrate, optical
(c) geometrical, optical
(d) coordinate, geometrical
Answer: c

Question. Which of the following complexes exhibits the highest paramagnetic behaviour ?
(a) [V(gly)₂(OH)₂(NH₃)₂]⁺
(b) [Fe(en)(bpy)(NH₃)₂]²⁺
(c) [Co(ox)₂(OH)₂]^2–
(d) [Ti(NH₃)6]³⁺
where gly = glycine, en = ethylenediamine and bpy = bipyridyl moities)
(At.nosTi = 22, V = 23, Fe = 26, Co = 27)
Answer: b

Question. Which of the following complex will show geometrical as well as optical isomerism (en=ethylenediammine)
(a) Pt(NH₃)₂Cl₂
(b) [Pt(NH₃)Cl₄]
(c) [Pt(en)₃]⁴⁺
(d) [Pt(en)₂Cl₂]
Answer: d

Question. The number of geometrical isomers from [Co(NH₃)₃(NO₂)₃] is
(a) 2
(b) 3
(c) 4
(d) 0
Answer: a

Question. Which one of the following octahedral complexes will not show geometric isomerism? (A and B are monodentate ligands)
(a) [MA₅B]
(b) [MA₂B₄]
(c) [MA₃B₃]
(d) [MA₄B₂]
Answer: a

Question. CuSO₄⋅5H₂O is blue in colour while CuSO₄ is colourless due to
(a) presence of strong field ligand in CuSO₄⋅5H₂O
(b) due to absence of water (ligand), d-d transition are not possible in CuSO₄
(c) anhydrous CuSO₄ undergoes d-d transitions due to crystal field splitting
(d) colour is lost due to loss of unpaired electrons.
Answer: b

Question. For the square planar complex [M (a) (b) (c) (d)] (where M = central metal and a, b, c and d are monodentate ligands), the number of possible geometrical isomers are
(a) 1
(b) 2
(c) 3
(d) 4
Answer: d

Question. The compounds [PtCl₂(NH₃)₄]Br₂ and [PtBr₂(NH₃)₄]Cl₂ constitutes a pair of
(a) coordination isomers
(b) linkage isomers
(c) ionization isomers
(d) optical isomers
Answer: c

Question. Which one of the following will not show geometrical isomerism ?
(a) [Cr(NH₃)₄Cl₂]Cl
(b) [Co(en)₂Cl₂]Cl
(c) [Co(NH₃)₅NO₂]Cl₂
(d) [Pt(NH₃)₂Cl₂ ]
Answer: c

Question. CN^– is a strong field ligand. This is due to the fact that
(a) it carries negative charge
(b) it is a pseudohalide
(c) it can accept electrons from metal species
(d) it forms high spin complexes with metal species
Answer: b

Question. The compound which is not coloured is
(a) K₄[Fe(CN)₆ ]
(b) K₃[Fe(CN)₆ ]
(c) Na₂ [CdCl₄ ]
(d) Na₂[CuCl₄ ]
Answer: c

Question. The number of isomers exhibited by [Cr(NH₃)₃Cl₃] is
(a) 2
(b) 3
(c) 4
(d) 5
Answer: d

Question. The number of geometrical isomers for [Pt(NH₃)₂Cl₂] is
(a) 2
(b) 1
(c) 3
(d) 4
Answer: a

Question. Due to the presence of ambidentate ligands coordination compounds show isomerism. Palladium complexes of the type [Pd(C₆H₅)₂(SCN)₂] and [Pd(C₆H₅)₂(NCS)₂] are
(a) linkage isomers
(b) coordination isomers
(c) ionisation isomers
(d) geometrical isomers 
Answer: a

Question. Which of the following facts about the complex [Cr(NH₃)₆]Cl₃ is wrong?
(a) The complex involves d²sp³ hybridisation and is octahedral in shape.
(b) The complex is paramagnetic.
(c) The complex is an outer orbital complex
(d) The complex gives white precipitate with silver nitrate solution.
Answer: c

Question. Atomic number of Cr and Fe are respectively 25 and 26,which of the following is paramagnetic?
(a) [Cr(CO)₆]
(b) [Fe(CO)₅]
(c) [Fe(CN)₆]^–4
(d) [Cr(NH₃)₆]⁺³
Answer: d

Question. Which of the following pairs represent linkage isomers?
(a) [Pd(PPh₃)₂(NCS)₂] and [Pd ( PPh₃)₂ (SCN)₂]
(b) [Co(NH₃)₅NO₃] SO₄ and [Co(NH₃)₅SO₄]NO₃
(c) [PtCl₂(NH₃)₄] Br₂ and [Pt Br₂ (NH₃)₄] Cl₂
(d) [Cu(NH₃)₄][Pt Cl₄] and [Pt(NH₃)₄][CuCl₄]
Answer: a

Question. [Sc(H₂O)₆]³⁺ ion is :
(a) colourless and diamagnetic
(b) coloured and octahedral
(c) colourless and paramagnetic
(d) coloured and paramagnetic
Answer: a

Question. What kind of isomerism exists between [Cr(H₂O)₆ ]Cl₃ (violet) and [Cr(H₂O)₅Cl]Cl₂.H₂O (greyish-green) ?
(a) linkage isomerism
(b) solvate isomerism
(c) ionisation isomerism
(d) coordination isomerism
Answer: b

Question. Type of isomerism which exists between [Pd(C₆H₅)₂(SCN)₂] and [Pd(C₆H₅)₂(NCS)₂] is :
(a) Linkage isomerism
(b) Coordination isomerism
(c) Ionisation isomerism
(d) Solvate isomerism 
Answer: a

Question. The IUPAC name of K₃[Ir(C₂O₄)₃] is
(a) potassium trioxalatoiridium (III)
(b) potassium trioxalatoiridate (III)
(c) potassium tris (oxalato) iridium (III)
(d) potassium tris (oxalato) iridate (III)
Answer: b

Question. Consider the following coordination compounds.
(i) [Pt(NH₃)₄Cl₂]Br₂
(ii) [Pt(NH₃)₄Br₂]Cl₂
(iii) [Co(NH₃)₄Cl₂]NO₂
Which of the following observations is correct?
(a) (i) will give a pale yellow and (ii) will give a white precipitate with AgNO₃ solution.
(b) (iii) will give a white precipitate with AgNO₃ solution.
(c) (i), (ii) and (iii) will give white precipitate with AgNO₃ solution.
(d) None of the above coordination compounds will give white precipitate with AgNO₃ solution.
Answer: a

Question. Which of the following rules is not correct regarding IUPAC nomenclature of complex ions?
(a) Cation is named first and then anion.
(b) In coordination sphere, the ligands are named alphabetically.
(c) Positively charged ligands have suffix ‘ate’.
(d) More than one ligand of a particular type are indicated by using di, tri, tetra, etc.
Answer: c

Question. Which of the following sets of examples and geometry of the compounds is not correct?
(a) Octahedral – [Co(NH₃)₆]³⁺, [Fe(CN)₆]^3–
(b) Square planar – [Ni(CN)₄]^2–, [Cu(NH₃)₄]²⁺
(c) Tetrahedral – [Ni(CO)₄], [ZnCl₄]^2–
(d) Trigonal bipyramidal – [Fe(NH₃)₆]²⁺,[CuCl₄]^2–
Answer: d

Question. The correct IUPAC name of the coordination compound K₃[Fe(CN)₅NO] is
(a) potassium pentacyanonitrosylferrate(II)
(b) potassium pentacyanonitroferrate(III)
(c) potassium nitritopentacyanoferrate(IV)
(d) potassium nitritepentacyanoiron(II).
Answer: a

Question. Which of the following complexes will have tetrahedral shape?
(a) [PdCl₄]^2–
(b) [Pd(CN)₄]^2–
(c) [Ni(CN)₄]^2–
(d) [NiCl₄]^2–
Answer: d

Question. The lowest value of paramagnetism is shown by
(a) [Co(CN)₆]^3–
(b) [Fe(CN)₆]^3–
(c) [Cr(CN)₆]^3–
(d) [Mn(CN)₆]^3–
Answer: a

Question. When excess of aqueous KCN solution is added to an aqueous solution of copper sulphate, the complex [Cu(CN)₄]^2– is formed. On passing H₂S gas through this solution no precipitate of CuS is formed because
(a) sulphide ions cannot replace CN^– ions
(b) [Cu(CN)₄]^2– does not give Cu²⁺ ion in the solution
(c) sulphide ions from H₂S do not form complexes
(d) sulphide ions cannot replace sulphate ions from copper sulphate solution.
Answer: b

Question. Which of the following has largest paramagnetism?
(a) [Cr(H₂O)₆]³⁺
(b) [Fe(H₂O)₆]²⁺
(c) [Cu(H₂O)₆]²⁺
(d) [Zn(H₂O)₂]²⁺
Answer: b

Question. When aqueous solution of potassium fluoride is added to the blue coloured aqueous CuSO₄ solution, a green precipitate is formed. This observation can be explained as follows.
(a) On adding KF, H₂O being weak field ligand is replaced by F– ions forming [CuF₄]^2– which is green in colour.
(b) Potassium is coordinated to [Cu(H₂O)₄]²⁺ ion present in CuSO₄ and gives green colour.
(c) On adding KF, Cu²⁺ are replaced by K⁺ forming a green complex.
(d) Blue colour of CuSO₄ and yellow colour of KI form green colour on mixing.
Answer: a

Question. Which of the following ligands form a chelate?
(a) Acetate
(b) Oxalate
(c) Cyanide
(d) Ammonia
Answer: b

Question. The ligand N(CH₂CH₂NH₂)₃ is
(a) bidentate
(b) tridentate
(c) tetradentate
(d) pentadentate.
Answer: c

Question. Hexacyano complexes of metals in their +2 oxidation state are usually yellow while the corresponding hexaaqua compounds are often blue or green. This is so because
(a) hexacyano complexes absorb orange or red light thus appear yellow while hexaaqua complexes absorb indigo thus appear yellow
(b) hexacyano complexes absorb indigo thus appearing yellow while hexaaqua complexes absorb orange or red light thus appear blue or green
(c) hexacyano complexes absorb yellow light while hexaaqua complexes absorb blue light
(d) CN– ions are yellow in colour while aqua ions are blue or green in colour.
Answer: b

Question. If a ligand is weak, the complex will be high spin while if the ligand is strong then the complex will be low spin. Here few complexes are listed:
I. [Cr(H₂O)₆]²⁺
II. [CoCl₄]^2–
III. [Fe(H₂O)₆]²⁺
IV. [Mn(H₂O)₆]²⁺
V. [Ni(CO)₄]
VI. [Ni(CN)₄]^2–
The complexes which have zero magnetic moment are.
(a) I and V
(b) II and VI only
(c) III and IV
(d) V and VI only
Answer: d

Question. Among the following compounds which is both paramagnetic and coloured?
(a) K₂Cr₂O₇
(b) [Co(SO₄)]
(c) (NH₄)₂[TiCl₆]
(d) K₃[Cu(CN)₄]
Answer: b