MCQ ON S & P BLOCK ELEMENTS

Nitrogen can be obtained from air by removing [AFMC 1998] (a) Oxygen (b) Hydrogen (c) Carbon dioxide (d) Both (a) and (c) acts as temporary bleaching agent but acts as permanent bleaching agent. Why [JEE Orissa 2004] (a) bleaches due to reduction but due to oxidation (b) bleaches due to reduction but due to reduction (c) Both of these (d) None of these Caro's acid is [DCE 2002] (a) (b) (c) (d) Inorganic benzene is [Pb. CET 2004] (a) (b) (c) (d) Which of the following ions, will have maximum hydration energy [Pb. CET 2003] (a) (b) (c) (d) When orthophosphoric acid is heated to the product formed is [CBSE PMT 1989] (a) Phosphine, (b) Phosphorus pentoxide, (c) Phosphorus acid, (d) Metaphosphoric acid, The statement true for is [AIIMS 2004] (a) It has a non-linear structure (b) It is called pseudohalogen (c) The formal oxidation state of nitrogen in this anion is -1 (d) It is isoelectronic with here, 'A' is [BVP 2004] (a) (b) (c) (d) A hydride of nitrogen which is acidic is [MP PMT 2004] (a) (b) (c) (d) The ONO angle is maximum in [AIIMS 2004] (a) (b) (c) (d) When ammonia is passed over heated , it is oxidised to [Roorkee 1992; BCECE 2005] (a) (b) (c) (d) Slaked lime is used in the manufacture of [MNR 1985] (a) Cement (b) Fire bricks (c) Pigment (d) Medicine Which of the following is the most stable [Roorkee Qualifying 1998] (a) (b) (c) (d) When is bubbled through a solution of barium peroxide in water [AFMC 2005] (a) is released (b) Carbonic acid is formed (c) is formed (d) No reaction occurs The lightest metal is [MP PET 2001] (a) (b) (c) (d) Which of the following will not undergo hydrolysis in water [DPMT 2001] (a) Ammonium sulphate (b) Sodium sulphate (c) Calcium sulphate (d) All the salts will hydrolyse The species that does not contain peroxide ion is [DCE 2003] (a) (b) (c) (d) The number of hydroxide ions produced by one molecule of sodium carbonate on hydrolysis is [AFMC 2000] (a) 1 (b) 2 (c) 3 (d) 4 Lead is soluble in [BVP 2004] (a) (b) (c) (d) The difference of water molecules in gypsum and plaster of paris is [CPMT 1997] (a) (b) 2 (c) (d) When burning magnesium ribbon is introduced into a jar of oxygen, it produces [MH CET 1999] (a) (b) (c) (d) Which of the following compounds transform baking soda into baking powder [AIIMS 2001] (a) KCl (b) (c) (d) Hydrated is used as [RPET 2003] (a) Catalyst in cracking of petroleum (b) Catalyst in Friedel Craft reaction (c) Mordant (d) All of these Which of the following ions has largest heat of hydration [MP PET 2001] (a) (b) (c) (d) The hydroxides which sublime on heating are [Roorkee 1999] (a) (b) (c) (d) Electrolysis of gives [KCET 1993] (a) Only (b) Potassium only (c) and (d) and Which species does not exist [JIPMER 2000] (a) (b) (c) (d) formation involves evolution of a large quantity of heat, which makes its use in [DPMT 2002] (a) Deoxidiser (b) Indoor photography (c) Confectionary (d) Thermite welding Nitrates of all metals are [DCE 2000] (a) Unstable (b) Stable (c) Coloured (d) Soluble The density of Neon will be highest at [JIPMER 2002] (a) STP (b) atmosphere (c) atmosphere (d) atmosphere When chlorine water is exposed to sunlight the colour change that occurs is [Kerala (Med.) 2002] (a) Colourless to brown (b) Brown to colourless (c) Light blue to colourless (d) Colourless to greenish yellow (e) Greenish yellow to colourless Sodium nitrate decomposes above to give [IIT 1998] (a) (b) (c) (d) forms , whereas P can form both and . Why [JEE Orissa 2004] (a) P has low lying 3d orbitals, which can be used for bonding but does not have low lying 3d orbital (b) atom is larger than P in size (c) P is more reactive towards Cl than (d) None of these Temperature of maximum density in and respectively are (a) 277.15 K, 284.75 K (b) 273.15 K, 277.15 K (c) 277.15 K, 285.75 K (d) 284.75 K, 277.15 K Non-metallic oxides dissolves in water to form (a) Acidic solution (b) Alkaline solution (c) Neutral solution (d) None of these Ordinary water is not used as a moderator in nuclear reactors because (a) It cannot slow down fast moving neutrons (b) It cannot remove the heat from the reactor core (c) It absorbs the fast moving neutrons (d) Of its corrosive action on the metallic parts of the nuclear reactor Brackish water mostly contains (a) Calcium chloride (b) Barium sulphate (c) Sodium chloride (d) Mineral acids is an example of (a) Ionic hydride (b) Covalent hydride (c) Metallic hydride (d) Polymeric hydride The volume strength of perhydrol is (a) 20 (b) 30 (c) 100 (d) 10 The solubility of an ionic compound is compared in heavy and simple water. It is (a) Higher in heavy water (b) Lower in heavy water (c) Same in heavy water and simple water (d) Lower in simple water Which of the following cannot be reduced by (a) (b) (c) Acidified (d) Acidified Hydrogen can be prepared by the action of dil. on (a) Copper (b) Iron (c) Lead (d) Mercury The element whose hydride contains maximum number of hydrogen per atom of the element is (a) Na (b) O (c) B (d) Si Indicator type silica gel used as a dehumidifier contains (a) ions (b) ions (c) ions (d) ions To an aqueous solution of some is added, till a brown ppt. is obtained. To this is added dropwise. The ppt. turns black with the evolution of . The black ppt. is (a) (b) (c) AgOH (d) None of these Atomic hydrogen reacts with oxygen to give (a) Almost pure water (b) Almost pure hydrogen peroxide (c) A mixture of water and hydrogen peroxide (d) None of these Which of the following cannot be used for the preparation of (a) (b) (c) (d) The process used for the removal hardness of water is [EAMCET 2001] (a) Calgon (b) Baeyer (c) Serpeck (d) Hoope 1. (d) Nitrogen can be obtained from air by removing oxygen and Hydrogen. 2. (b) bleaches due to oxidation which is permanent bleaching while bleach due to reduction which is temporary bleach and convert in original by atmospheric oxygen. 3. (c) Caro’s acid is 4. (c) Inorganic benzene is 5. (d) Hydration energy of smaller cations are higher than those of larger cations, hence has maximum hydration energy among these. 6. (d) 7. (c) derived from in which nitrogen shows –1 oxidation state. 8. (b) This is the laboratory method of preparing phosphine gas. In this reaction, phosphorus disproportionate into phosphine and sodium hydrogen phosphite. 9. (c) Hydrazoic acid is a fairly strong acid which is strong than but weak than mineral acid. 10. (d) have 132° bond angle increase of electron or increase of more electronegative atom in it decrease its bond angle since loose a electron by which its bond angle increase from 132°. 11. (a) 12. (a) Composition of portland cement is Lime 50-60% MgO 2-3% 20-25% 1-2% Alumina 5-10% 1-2% 13. (a) on going down the group due to inert pair effect + 2 state is more stable than + 4. 14. (c) When is bubbled through a cold pasty solution of barium peroxide in water, is obtained. Barium carbonate being insoluble is filtered off. This is known as Merck’s process. 15. (a) Lithium is the Lightest metal with atomic No. 3. 16. (b) Sodium sulphate is a salt of strong acid and strong base (NaOH). As we know that salt of strong acid and strong base do not hydrolyse in water but will ionised. 17. (a) (Lead dioxide ) is not a peroxide. All other are peroxides as they have linkage. 18. (b) 19. (d) Lead is soluble in dil. . However, it becomes passive towards conc. . 20. (d) . 21. (b) 22. (d) transform baking soda into baking powder. 23. (c) Hydeated in used as mordant. 24. (d) decreasing order of heat of hydration. 25. (d) sublimes on heating. 26. (c) ; ; Since, reduction potential of is higher. Hence it gets reduced easily. 27. (b) does not exist because carbon has a valancy of 4. 28. (a) In thermite welding large quantity of heat is used which is evolved during formation. 29. (b) Generally all metal nitrates are stable. 30. (b) Density of Neon will be highest as , 2 atmosphere. 31. (e) . 32. (a) 33. (a) P has low lying 3d orbitals, which can be used for bonding, where as does not have low lying 3d orbitals. 34. (a) Temperature of maximum density of is 277.15 K. Temperature of maximum density of is 284.75 K. 35. (a) Non metallic oxides in water are form acidic solutions e.g. 36. (c) Ordinary water absorbs fast moving neutrons, thus stopping the process of nuclear fission. 37. (c) Brackish water mostly contains sodium chloride. 38. (c) It is a metallic hydride. 39. (c) The volume strength of perhydral is 100 perhydral is 30% 10 vol. ( 30% of vol. 40. (b) The solubility of an ionic compound is more in simple water and less in heavy water. 41. (b) cannot reduce . All other compounds are reduced by . 42. (b) Hydrogen cannot be prepared by the action of dil. on copper or mercury as these two metals cannot displace hydrogen from acids. Action of dil. are stops after sometimes due to the formation of insoluble . Only, iron reacts rapidly with dil. to give . 43. (d) Hydride of contains more hydrogen atoms than hydrides of . 44. (c) Indicator type of gel used as a dehumidifier contains ions, when dry it is blue in colour and on absorbing moisture it becomes pink. 45. (d) The finely divided Ag is black in colour. 46. (b) Atomic hydrogen reacts with oxygen to give almost pure hydrogen peroxide. 47. (c) 48. (a) Calgon process is used for the removal of hardness of water. S & P BLOCK ELEMENTS 3 *** Mrs Shallu Aggarwal Mobile #. 98786-08983 *** 132° O O N