MCQ Test PDF

1. Which colour is observed for the [Cu(H₂O)₆]²⁺ complex? - A) Green - B) Blue - C) Yellow - D) Red - Answer: B) Blue 2. Which ligand causes the complex [CuCl₄]²⁻ to be formed from [Cu(H₂O)₆]²⁺? - A) NH₃ - B) EDTA⁴⁻ - C) H₂O - D) Cl⁻ - Answer: D) Cl⁻ 3. What is the colour change observed when exce...

1. Which colour is observed for the [Cu(H₂O)₆]²⁺ complex? - A) Green - B) Blue - C) Yellow - D) Red - Answer: B) Blue 2. Which ligand causes the complex [CuCl₄]²⁻ to be formed from [Cu(H₂O)₆]²⁺? - A) NH₃ - B) EDTA⁴⁻ - C) H₂O - D) Cl⁻ - Answer: D) Cl⁻ 3. What is the colour change observed when excess NH₃ is added to [Cu(H₂O)₆]²⁺? - A) Blue solution to dark blue solution - B) Yellow solution to green solution - C) Green precipitate to brown precipitate - D) No change - Answer: A) Blue solution to dark blue solution 4. What is the oxidation state of vanadium in the ion [VO₂]⁺? - A) +2 - B) +4 - C) +5 - D) +6 - Answer: C) +5 5. What is the coordination number in the complex [Fe(H₂O)₆]³⁺? - A) 2 - B) 4 - C) 6 - D) 8 - Answer: C) 6 6. Which factor does NOT affect the colour of a transition metal complex? - A) Oxidation state of the central metal ion - B) Type of ligand bonded - C) Coordination number of the complex ion - D) Amount of metal ion - Answer: D) Amount of metal ion 7. Which complex ion has a deep blue colour when reacts with excess NH₃? - A) [Fe(H₂O)₆]³⁺ - B) [Cu(NH₃)₄(H₂O)₂]²⁺ - C) [FeCl₄]⁻ - D) [Ni(C₂O₄)₃]⁴⁻ - Answer: B) [Cu(NH₃)₄(H₂O)₂]²⁺ 8. What is the effect of adding concentrated HCl to [Fe(H₂O)₆]³⁺? - A) Deep blue solution to green solution - B) Yellow solution to purple solution - C) Yellow solution to yellow-green solution - D) No change - Answer: D) No change 9. Which ligand can act as a multidentate ligand and form a more stable complex? - A) NH₃ - B) H₂O - C) Cl⁻ - D) EDTA⁴⁻ - Answer: D) EDTA⁴⁻ 10. What is the observed colour for the [Fe(H₂O)₆]²⁺ complex? - A) Green - B) Red - C) Purple - D) Colorless - Answer: A) Green