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UNIT IA AND IIA OR GROUPS 1 AND 2 : S-BLOCK ELEMENTS (Alkali metals; Alkaline earth metals) Select the lettered item which best completes each of the following: 1. The outer shell electronic configuration of Cs (Z =55) (a) [Ne] 3 S1 (b) [Ar] 4 S1 (c) [kr] 5 S1 (d) [Xe] 6 S1 The last electron has the quantum numbers n = 5, l =0, m =0, s = +1/2. the atomic numbe of the element is (a) 19 (b) 37 (c) 55 (d) 11 Alkali metals areusually prepared by (a) reduction of their oxides by carbon (b) reduction of their oxides with Al (c) electrolysis of their molten chlorides (d) thermal decomposition of their carbonates Which compound possesses the highest lattice energy? (a) CsI (b) KF (c) LiF (d) NaCl Which of the following compounds has the highest melting point ? (a) NaF (b) NaCl (c) NaBr (b) NaI The alkali metals are strong reducing agents due to (a) low ionization energy (b) large ionic radii (c) high enthalpy of hydration (d) potential value The covalent radius of the potassium atom is 0.203 manometer. The radius of K+ ion will be (a) 0.013 (b) 0.254 (c) 0.133 (d) 0.231 8. Which one of the following has lowest first ionization energy? (a) Li (b) Na (c) Rb (d) Cs Li (s) Li+(aq) + e , E = 3.67V, Li is the best reducing agent due to its (a) low I.E. (b) small ionic radius (c) low heat of sublimation of Li (d) high enthalpy of bydration of Li+
2.
9.
3.
10. The physical property of the group IA metals which increases numericaly as the groupis descended is (a) first I.E. (b) ionic radii (c) melting point (d) hydration enthalpy of M+ ions 11. Which of the following does not produce an alkaline solution in water? (a) NaHCO3 (b) NaOH (c) Na2CO3 (d) NaHSO4 12. Which one of the following concerning the compounds of Lithium is false ? (a) the hydroxide, carbonate, nitrate decomposes to give the oxide on heating (b) it is the most electro- negative element of group IA (c) the hydrogen carbonate cannot be isolated as a stable solid (d) it forms a peroxide but not a superoxide 13. Which alkali metal has the lowest melting point and exists as aliquid ? (a) Na (b) K (c) Rb (d) Cs 14. Which of the following Carbonates does not yield CO2 on heating ? (a) Li2CO3 (b) Na2 CO3
4.
5.
6.
7.
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(c) MgCO3 (d) CaCO3 15. A solution of Na in liquid NH3 serves a good reducing agent due to reaction (a) 2Na + 2NH3 2NaNH2 + H2 (b) NaNH2 + N2O NaN3 + H2O (c) 2Na + 2N2O 2NaOH + H2 (d) solvated electron 16. A neutral white solid (sodium salt) on heating liberates a gas and leaves an alkaline residue. The gas turn lime water milky. The solid is (a) Na2CO3 (b) NaHSO4 (c) NaHCO3 (d) NaNH4HPO4 17. A solid on heating gives a gas which supports combustion of Mg and P4 is (a) NH4NO2 (b) NaNO3 (c) NH4NO3 (d) Pb(NO3)2 18. In the solva process , the chief products are (a) CaCO3 and Ca(HCO3)2 (b) Na2CO3 and NaHSO4 (c) Na2SO4 and NaHSO4 (d) CaCl2 and Ca(NO3)2 19. Among the alkali metals, the metal with the lowest boiling point is (a) Na (b) K (c) Rb (d) Cs 20. The metal which is difficult to be extracted from its oxide (a) Fe (b) Zn (c) Cs (d) Mg 21. Reaspm fpr a;la;o ,eta;s tp ne spft os (a) they are less metallic in nature (b) there is only one valency electron per nucleus (c) they do not have close packed structures (d) they have high I.E. 23. AB AB....... close packing of identical spheres give rise to (a) a face centred cubic structure (b) a body-centred cubic structure
(c) a hexagonal clowepacked structure (d) a cubic close packed structure 24. The CsCl unit cell is best decribed as (a) primitive cubic (b) body-centered cubic (c) face -centered (d) orthorhombic 25. One would expect the elemental form of Cs room temperature to be a (a) Net-work solid (b) metallic solid (c) non-polar liquid (d) ionic liquid 26. A compound formed by uniting the elements having Z=55 with the element having Z=16 will involve bonds that are (a) polar covalennt (b) non-polar covalent (c) Co-ordinate covalent (d) electrovalent 27. Banking powder is (a) NaHCO3 (b) potassium acid tartarate (c) mixture (a) and (c) (d) mixture of NaHCO3 28. The reaction occuring in soda-acid fire extinguisher is (a) 2NaHCO3 + H2SO4 Na2SO4 + 2H2O + CO2 (b) 4NaHCO3 + Al2(SO4)3 2Na2SO4 + 2Al(OH)3 + 6O2 (c) 6CO2 + 6H2O C6H12O6 + 6O2 (d) NaHCO3+ KHC4H4O8 NaKC4H4O6 + H2O + CO2 29. An alkali metal salt which is neither efflorescent nor deliquescent or hygroscopic is (a) Na2CO3.10H2 O (b) Na2SO4.10H2O (c) NaOH (d) NaCl 30. A metal that readily reacts with cold water is (a) K (b) Mg (c) Fe (d) Zn 31. Which of the following configurations corresponds to alkaline earth metals
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(a) [Ne]3S23p2 (b) [Ar]3d24S2 (c) [Ar]3d104s2 (d) [Ar]4s2 32. The member of group II which has the simplest electronic configurtion is (a) Ca (b) Mg (c) Ba (d) Be 33. Addition of excess NaOH produces precipitate in which one of the following (a) SnCl2 (b) Al2(SO4)3 (c) ZnSO4 (d) FeBr3 34. The most probable reason that the alkaline earth metals give dipositive ions instead of unipositive (a) the 1st and 2nd I.E. are not very much different (b) compounds of M+ ions are not stable (c) compounds with dipositive ions have more lattice energy than those with unipositive (d) The dipositive ions have more charge on it than the unipositive ions 35. Alkaline earth metals form hydrated crystalline solids such as MgCl2.6H2O.CaCl2.6H2O. This is (a) smaller ionic size (b) increased charge on ions (c) higher hydration enthalpies (d) high oxidation potential 36. The thermal stability of alkaline earth carbonates increases from Be to Ba because (a) Covalent nature decreases and ionic nature increases (b) lattice energy increases (c) electropositive nature increases (d) none of these 37. Which alkaline earth metal produces covalent compounds ? (a) Ca (b) Mg (c) Sr (d) Be 38. The best reagent to absorb traces of water is (a) Mg(ClO4)2 (b) silica gel
(c) CaCl2 (d) H2SO4 39. Whcih of the following correctly represents the 2nd I.E. of Cas ? (a) Ca(s) Ca2+ (s) + 2e (b) Ca(s) Ca2+ (s) + 2e (c) Ca+(g) Ca2+ (g) + e (d) Ca(g) Ca2+ (s) + 2e 40. Which of the following compounds possesses the greater degree of covalent character in its (a) BeF2 (b) MgF2 (c) CaF2 (d) BaF2 41. A 0.01 M solution of a reagent gives a precipitate when CO2 is dubbled inot it. The reagent could ions is (a) KOH (b) CsOH (c) Na2CO3 (d) Ba(OH)2 42. Which of the following decreases ions decending from Be to Ba ? (a) solubility of Hydroxides in water (b) basic strenght of oxides (c) thermal stabilities of the carbonates (d) sum of the first two ionization energies 43. Which one of the following statements to due is correct ? The chlorides of II goup metals (a) are all hygroscopc the with exception of BeCl2which hydrolysis in air (b) increase in lattice enthalpy from BeCl2 to BaCl2 (c) decrease in melting point from BeCl2 to BaCl2 (d) are all insoluble except BaCl2 44. Which of the follow statement is incorrect for Be ? (a) most of its compounds are largely covalent (b) it forms a covalent structure and is a linear molecule (c) it has distinctive group properties due to smaller size and high electronegativity (d) it fors Be2+ ions because of the low value of the sum of 1st and 2nd I.E. 45. Co,plexes conataining Be and having tetrahedral geometry are
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(a) [Be(H2O)4]2+ (b) [BeF4]2 (c) [BeCl4]2 (d) all the above 46. Gypsum CaSO4.2H2O on heating to 120C forms plaster of paris which has composition (a) 2CaSO4 . 3H2O (b) CaSO4.H2O (c) 2CaSO4.H2O (d) CaSO4 47. Insoluble rock phosphate is coverted into an Important fertilizer by treatment with (a) HNO3 (b) H2SO4 (c) NaOH (d) HF 48. The formula of Epsom salt is (a) MgSO4.7H2O (b) Mg(ClO4)2 (c) MgCO3 .CaCO3 (d) KCl2MgCl2.6H2O 49. Of the following, the metal that does not give a red flame test is (a) Li (b) Sr (c) Rb (d) Ba 50. Lithopone, a white higment, is (a) Zns (b) BaSO4 (c) Mixture of ZnS and BaSO4 (d) mixture of BaSO4 and SrSO4 51. Solubility of sulphates in water decreases from MgSO4 to BaSO4 it is due to the fact that (a) ionic nature increases (b) Size of M2+ ion increases (c) lattice energy decrease (d) hydration enthalpy of M2+ ions decreases 52. Portland cement consists of (a) CaO, SiO2 , SO3, and Fe2O3 (b) Cao, SO3, MgO, Na2O (c) SiO2, MgO, Na2O, SO3 (d) CaO, SiO2, Al2O3,Fe2O3 , SO3,Na2O 53. Portland cement is (a) Calcium aluminium Silicate (b) Calcium aluminate + Ca. silicate
(c) CaO + Al2O3 + SiO2 (d) Calcium silicate + gupsum 54. Gypsum is added to cement (a) to prevent it from undergoing hydrolysis (b) to increase it strength (c) to accelerate the process of setting of cement (d) to retard the presenting of cement
55. When CaC2 is heated in a current of nitrogen a t 1000, at the product formed is (a) CaCN2 (b) CaN (c) CaCN + C (d) Ca(NO2)2 56. Compared with the alkaline earth metals, the alkali metals have (a) greater hardness (b) higher melting point (c) SMALLER IONIC RADII (d) lower ionization energy 57. A m,etal is obtained commercially from sea water (a) Na (b) Mg (c) Ba (d) Ra 58. Lithia water used in medicine as a remedy for gout and rheumatism is (a) lithium carbonate (b) lithium bicarbonate (c) lithium chloride (d) lithium salicylate 59. When Mg(NH4 )PO4 is heated, the product is (a) Mg3(PO4)2 (b) MgHPO4 (c) Mg2P2O7 (d) (NH4)3PO4 60. Which of the following compounds decomposes on heating similar to LiNO3 (a) Be(NO3)2 (b) Sr(NO3)2 (c) Mg(NO3)2 (d) all 61. The chemical formula of "Norweganian salt" is (a) Ca(NO3)2.CaO (b) 2CaSO4.H2O
MgO,
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(c) (CH3COO)2 Ba (d) Ca(H2PO4)2 . H2O + 2CaSO4.2H2O 62. The least obundant IIA group element in the earth's crust is (a) Sr (b) Ca (c) Ra (d) Ba 63. The salt which is produced as bye-product in solvay process (a) CaCO3 (b) CaCl2 (c) CaSO4 (d) Na2CO3 64. The superoxide ion, found in KO2 , has the structure: (a) O O (b) O = O (c) O O (d) [O ...O] 65. Which metal is most difficult to extract from its oxide ? (a) Ca (b) Mg (c) Ag (d) Cs 66. Mark the nitrate which decomposes differently on heating ? (a) NaNO3 (b) KNO3 (c) LiNO3 (d) RbNO3 67. K2CO3 can't be prpared by solvay process because (a) KHCO3 is unstable (b) KHCO3 is very soluble (c) KHCO3 can't be prepared by passing NH3 and CO2 through Kcl solution (d) K2CO3 is more soluble than Na2CO3 68. Which one of the following oxides is thermally most stable ? (a) Na2 O (b) Ag2 (c) HgO (d) Au2O3 69. LiF is insoluble in water while NaF, KF are soluble. This is due to its (a) Low H lattice (b) high H lattice (c) smaller ionic size of Li+ (d) high covalent nature
70. Which alkali metal ion in solution conducts electric current most readily ? (a) Cs+ (b) Rb+ (c) K+ (d) Li+ 71. Polarizing powedr of an element is (a) (b) (c) (d)
ionic ch arg e ionic radius ionic ch arg e (ionic radius) 2
(ionic radius) 2 ionic ch arg e (ionic ch arg e) 2 ionic radius
72. The solubility of hydroxides of group 2 increases from Mg(OH)2 to Ba(OH)2 due to (a) increase in lattice energy (b) decrease in lattice energy (c) increase in I.E. (d) increase in thermal stability 73. Alkaline earth metals have standard electrode potential values very similar to there of alkali (a) high lattice energy of M2+ ions in the solid salts (b) high hydration energies of M2+ ions in solution (c) dimagnetic nature (d) none of these of M2+ ions 74. Be show a diagonal resemblance with Al. due to (a) similar ionic radii (b) similar polarizing power (c) similar boiling points (d) all of these 75. The gem stone emald has the same formula as (a) beryl ore (b) lipodolite ore (c) monazite sand (d) phenacite 76. Which metal of group 2 has & b.p., and larger1st and 2nd I.E.? (a) Be (b) Mg (c) Ca (d) Ba
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77, Be-compounds are covalent due to (a) high E.N. value (b) small ionic radius (c) high hydration energy of Be2+ ions (d) small highly charged ion 78. which one of the follwoing has 4 : 4 Zinc blende structure ? (a) BeO (b) CaO (c) SrO (d) BaO 79. BeSO4 and HgSO4 are more soluble in water than CaSO4, SrSO4, BaSO4. it is due to (a) high ionic charge on Be2+ and Mg2+ (b) high heat of hydrations of Be2+ and Mg2+ (c) high covalent nature of Be2+ and Mg2+ (d) high lattice energies of Be2+ and Mg2+ in the solid salts 80. Which of the following ha greater tendency for complex formation ? (a) Be (b) Mg (c) Ca (d) Ba 81. Which is a false statement ? (a) Na and K are Chemically similar but their biological function are different
(b) Na+ ions are actively expelled from cells whereas K+ are not (c) K ions inside the cell are essential for metabolism of glucose, synthesis of proteins and enzymes (d) The ion transport is active expulsion of K+ and active take-up of Na+ 82. Which is false statement ? (a) Mg2+ is important in chlorophy 11 (b) Ca2+ is important in bones of teeth (c) Ca2+ ions are important in blood clotting (d) Mg2+ ions are concentrated in the bodhy fluids outside the cell and Ca2+ ions are concentrated in animals cells 83. Which is a false statement ? (a) Be-salt are sweet toxic (b) In Chlorophyll, four N-atoms form porphyrin ring system are co-ordinated to Mg(II) (c) Ca2+ and Mg2+ in hard water estimated by titration with E.D.T.A. (d) (BeF4)2 readily co-ordinates two extra F ions to form (BeF6)4
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