MCQs on Crystal Field Theory

MCQs on Crystal Field Theory

1. Which of the following complexes shows zero crystal field stabilization energy?

(a) [Co(H₂O)₆]³⁺

(b) [Fe(H₂O)₆]³⁺

(c) [Co(H₂O)₆]²⁺

(d) [Mn(H₂O)₆]³⁺

Answer: (b)

2. Which of the following is paramagnetic?

(a) [CoBr]₄^2-

(b) Mo(Co)₆

(c) [Pt(en)Cl₂]

(d) [Co(NH₃)₆]³⁺

Answer: (a)

3. For a high spin d⁴ octahedral complex the crystal field splitting energy will be

(a) -1.6 Δ_o

(b) -0.8 Δ_o

(c) -0.6 Δ_o

(d) -1.2 Δ_o

Answer: (c)

4. Which of the following is a bidentate ligand?

(a) Br

(b) CH₃NH₂

(c) C₂O₄^2-

(d) CH₃CN

Answer: (c)

5. How many unpaired electrons are present in [CoF₆]^3- complex?

(a) 4

(b) zero

(c) 2

(d) 3

Answer: (a)

6. Which of the following d orbitals take part in the octahedral complex with d²sp³ hybridisation?

(a) dxy, dyz

(b) dxz, dx²−y²

(c) dx²−y², dz²

(d) dz², dxz

Answer: (c)

7. The compound, which does not contain a metal-carbon bond is

(a) K[Pt(C₂H₄)Cl₃]

(b) C₂H₅MgBr

(c) Ni(CO)₄

(d) Al(OC₂H₅)₃

Answer: (d)

8. The correct increasing order of splitting power of ligands according to spectrochemical series is

(a) Cl^– < OH^– < CN^–

(b) Cl^– < CN^– < OH^–

(c) OH^– < Cl^– < CN^–

(d) OH^– < CN^– < Cl^–

Answer: (a)

9. Which of the following complexes has a magnetic moment of 1.73 BM?

(a) [Ni(CN)₄]^2-

(b) TiCl₄

(c) [Cu(NH₃)₄]²⁺

(d) [CoCl₆]^4-

Answer: (c)

10. Tetraamminecopper(II) sulphate is _______ in colour.

(a) violet

(b) blue

(c) green

(d) red

Answer: (b)