Title UNIT 4 THE D-AND F-BLOCK ELEMENTS-1.pdf ✅

Page| 1 8.THE D-AND F-BLOCK ELEMENTS Single Correct Answer Type 1. On strongly heating AgNO3 we get: a) AgNO2 b) Silver nitride c) Ag d) Ag2O 2. Transition metals in their compounds show: a) Ionic bonds b) Covalent bonds c) Ionic and covalent bonds d) Ionic and coordinate bonds 3. 4K2Cr2O7 Heat → 4K2CrO4 + 3O2 + X In the above reaction, X is a) CrO3 b) Cr2O7 c) Cr2O3 d) CrO5 4. Cynaide process is used for the extraction of a) Au b) Ag c) Cu d) Both (a) and (b) 5. The colour of zinc sulphide is: a) Yellow b) White c) Brown d) Black 6. The metal extracted by cyanide process is a) Silver b) Copper c) Iron d) Sodium 7. Which metal gives hydrogen gas on heating with hot concentrated alkali? a) Ag b) Ni c) Zn d) Cu 8. Which of the following metal ions is not coloured? a) Ti3+ b) Fe3+ c) V 2+ d) Zn2+ 9. The process of extraction of Au and Ag ores is based on their solubility in: a) NH3 b) HCl c) HNO3 d) KCN 10. In the process of extraction of gold, Roasted gold ore +CN− + H2O O2 → [X] + OH− [X] + Zn ⟶ [Y] + Au Identify the complexes [X] and [Y] a) X = [Au(CN)2 ] −, Y = [Zn(CN)4 ] 2− b) X = [Au(CN)4 ] 3−, Y = [Zn(CN)4 ] 2− c) X = [Au(CN)2 ] −, Y = [Zn(CN)6 ] 4− d) X = [Au(CN)4 ] −, Y = [Zn(CN)4 ] 2−
Page| 2 11. To dissolve argentite ore which of the following is used? a) Na[Ag(CN)2] b) NaCN c) NaCl d) HCl 12. The magnetic moment μ, of transition metals is related to the number of unpaired elelctrnosn as a) μ = n(n + 2) 2 b) μ = n 2 (n + 2) c) μ = n (n + 2) d) μ = √n(n + 2) 13. Melting of Zn metal and then pouring it into cold water gives: a) Zn dust b) Granulated Zn c) Hard Zn metal d) Soft Zn metal 14. Percentage of gold in Fool’s gold is a) Zero b) 8 c) 16 d) 30 15. Copper sulphate is commercially made from copper scrap by: a) Dissolving in hot concentrated sulphuric acid b) Action of dilute sulphuric acid and air c) Heating with sodium sulphate d) Heating with sulphur 16. Which of the following compounds has colour but no unpaired electrons? a) KMnO4 b) K2MnO4 c) MnSO4 d) MnCl2 17. Mercury forms amalgams with all except: a) Al b) Zn c) Ni d) Fe 18. Granulated Zn is obtained by: a) Suddenly cooling molten Zn b) Adding molten Zn to water c) Heating Zn 100 to 150C d) Dropping molten Zn drop by drop 19. In the first transition series, the differentiating electron enters: a) 5d-orbital b) 4d-orbital c) 3d-orbital d) 2d-orbital 20. Identity the ore not containing iron. a) Limonite b) Siderite c) Carnallite d) Chalcopyrites
Page| 3 21. Purest form of iron is a) Cast iron b) Pig form c) Wrought iron d) Steel 22. Which metal adsorbs hydrogen? a) Pd b) K c) Al d) Zn 23. The most abundant ore of iron is: a) Haematite b) Limonite c) Magnetite d) Siderite 24. Metallic silver may be obtained from AgCl by a) Heating it in the current of H2 b) Fusing it with sand c) Treating with carbon monoxide d) Fusing it with Na2CO3 25. Choose the correct statement. a) Transition elements have low melting points. b) Transition elements do not have catalytic activity. c) Transition elements exhibit variable oxidation states. d) Transition elements show inert pair effect. 26. Bessemer’s converter is used in the manufacture of: a) Cast iron b) Pig iron c) Steel d) Wrought iron 27. Number of electrons present in the outermost orbit of Fe atom is: a) 3 b) 1 c) 2 d) 4 28. Which will reduce acidified potassium dichromate solution? a) Potash alum b) Mohr’s salt c) Chile saltpetre d) White vitriol 29. The lanthanoids contraction relates to a) Atomic radii b) Atomic as well as M3+ radii c) Valence electrons d) Oxidation states 30. Transition metals show paramagnetism due to a) High lattice energy b) Characteristics configuration c) Variable oxidation states d) Unpaired electrons 31. ‘Mercury’ tree can be prepared: a) By mixing up mercuric thiocyanate and gum b) By adding Nessler’s reagent to a ammonium salt solution c) By pouring little mercury into AgNO3 solution
Page| 4 d) By heating mercuric chloride 32. When excess of SnCl2 is added to a solution of HgCl2, a white ppt. turning to grey is obtained. This grey colour is due to the formation of: a) Hg2Cl2 b) SnCl4 c) Sn d) Hg2 33. Among the following, the compound that is both paramagnetic and coloured is a) (NH4 )2(TiCl6) b) K2Cr2O7 c) K3[Cu(CN)4] d) VOSO4 34. All the metals form oxides of the type MO except a) Copper b) Barium c) Silver d) Lead 35. Cinnabar is an ore of: a) Lead b) Zinc c) Silver d) Mercury 36. Heating mixture of Cu2O and Cu2S will give a) Cu2SO3 b) CuO + CuS c) Cu + SO3 d) Cu + SO2 37. The substance that sublimes on heating is: a) MgCl2 b) AgCl c) HgCl2 d) NaCl 38. Actinides a) Have variable valency b) Include element 12 c) Are all synthetic elements d) Have only short lived isotopes 39. The 3d-transition series contains elements from atomic number: a) 22 to 30 b) 21 to 30 c) 21 to 31 d) 21 to 29 40. Which of the following is not a characteristic of transition elements? a) Variable oxidation states b) Formation of coloured compounds c) Formation of interstitial compounds d) Natural radioactivity 41. An element which is highly toxic for plants and animals is: a) Au b) Mn c) Hg d) Ca 42. Native silver metal forms a water soluble complex with a dilute aqueous solution of NaCN in presence of: a) Nitrogen b) Oxygen c) CO2 d) Ar 43. Calamine is a) CaCO3 b) MgCO3 c) ZnCO3 d) CaCO3 + CaO 44. Which series of elements have nearly the same atomic radii? a) F, Cl, Br, I b) Na, K, Rb, Cs c) Li, Be, B, C d) Fe, Co, Ni, Cu 45. Which transition elements exhibit +8 oxidation states?