| PRACTICE PAPER IIT-JEE CHEMISTRY– 2007 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Question Type A : Single Answer is Correct 1. Which of the following statement is incorrect? (a) C — D bond vibrates more slowly than a C — H bond. (b) C — D bond has lower zero point energy than a C — H bond. (c) In aromatic electrophilic sulphonation primary isotopic effect occurs. (d) C — D bond has higher vibrational energy than C — H bond. 
 Here product A is
4. Among the given gem diols, which is/are stable with respect to their corresponding carbonyls?
Correct options are
 Rearranged alkene product after rearrangement at low temperature will be mainly,
6. Which of the following alcohols would you expect to form a carbocation most readily in sulphuric acid
7. Which of the following will accept H+ ion with fastest rate ?
8. In the reaction 
9. Which of the following compounds does not give Diel’s Alder reaction in presence of ethylene -
Correct option are
10. The correct order of increasing basic nature for the following compounds is: 
11. A solution of 0.4 mole of KI (100% dissociated) in 1000 g water freezes at T1°C. Now to this solution 0.2 mole HgI2 is added and the resulting solution freezes at T2°C. Which of the following is correct?
12. There is mixture of Cu(II) chloride and Fe(II) sulphate. The best way to separate the metal ions from this mixture in qualitative analysis is by treating it with : (a) hydrogen sulphide in mild acidic medium, where only Cu(II) sulphide will be precipitated (b) ammonium hydroxide buffer, where only Fe(II) hydroxide will be precipitated (c) hydrogen sulphide in mild acidic medium, where only Fe(II) sulphide will be precipitated (d) ammonium hydroxide buffer, where only Cu(II) hydroxide will be precipitated 13. Borax structure contains :
14. Gaseous ethylene, C2H4 reacts with hydrogen gas in the presence of platinum catalyst to form ethane  A mixture of C2H4 and H2 known only to contain more H2 than C2H4 has a pressure of 52 mm in an unknown volume. After the gas had been passed over a platinum catalyst, its pressure was 34 mm in the same volume and at the same temperature. Fraction of the ethylene molecules in the original mixture :
15. In a solid, oxide ions are arranged in ccp. One sixth of the tetrahedral voids are occupied by the cations A while one third of the octahedral voids are occupied by the cations B. The formula for the compound is :
16. In which of the following case, increase in concentration of ion cause increase in Ecell ?
17. Which of the following is not optically active?
18. Water and chlorobenzene are immiscible liquids. Their mixture boils at 90°C under a reduced pressure of 9.58 × 104 Pa. The vapour pressure of pure water at 90°C is 7.03 × 104 Pa and molecular weight of chlorobenzene is 112.5. The percent of chlorobenzene in the distillate is equal to :
9. Given that  If Fe2+, Fe3+ and Fe solid are kept together then:
20. A colourless water soluble solid ‘X’ on heating gives equimolar quantities of Y and Z. Y gives dense white fumes HCl and Z does so with NH3. Y gives brown precipitate with Nessler’s reagent and Z gives white precipitate with nitrates of Ag+, Pb2+ and Hg+. ‘X’ is:
Question Type B : More than ONE may be correct 21. Which of the following statements is/are correct? (a) Compounds of S, Se and Te with oxygen are generally tetravalent, but fluorine brings out maximum oxidation state of +6. (b) The higher oxidation states become less stable as we go down the group. (c) The +4 state shows both oxidizing and reducing properties but in +6 state the compounds are only oxidizing. (d) These compounds are typically volatile. 22. Potassium manganate can be converted into potassium permanganate by oxidation
23. A radioactive element X decays by the sequence and with half lives given below :  Which of the following statements about this system are correct? (a) Maximum amount of Y present at any time is less than 50% of the initial amount of X (b) Atomic number of X and Z are same (c) The mass number of Y is greater than X. (d) The mass number of Z is less than X. 24. Which of the following statements are correct? (a) The probability of finding a 4d electron right at the nucleus is zero. (b) For all values of n, the p-orbitals have the same shape, but the overall size increases as n increases, for a given atom. (c) A 2px atomic orbital consists of two lobes of electron density. (d) There is no probability of finding a p-electron right at the nucleus. 25. Which alkyl halide undergo E2 elimination
Following the graph, which of the statement/s is/are correct? (a) The absolute conversion of N2O4 into NO2 (N2O4  2NO2) is spontaneous(b) The dynamic conversion (N2O4  2NO2) at equilibrium point is spontaneous(c) Formation of N2O4 is more spontaneous than dissociation (d) Both process dissociation as well as formation are equally spontaneous 27. What could be the correct statements about idealized Carnot’s heat engine working between temperatures T2 (source) and T1 (sink)? (a) Efficiency  , which is maximum(b) Complete conversion of heat into work is possible i.e.,  can be unity(c) Power of the engine is maximum (d) Power of the engine is zero. 28. Addition of which of the following will separate the cations from an aqueous solution of Mg(ClO4)2 and AgNO3 ?
29. An isothermal vessel contains SO2(g) in equilibrium with Cl2(g) as  . At equilibrium, total pressure is 4 atm when volume is 1 L. If the volume is increased to 2 L, the new equilibrium pressure in the vessel is P. Then
30. Pick up the false statement. (a) In the fluorite structure (CaF2), the Ca2+ ions are located at the lattice points and the fluoride ions fill all the tetrahedral holes in the ccp crystal. (b) In the antifluorite structure (Li2O, Rb2S) the cations are located at the lattice points and anions fill the tetrahedral holes in the ccp structure. (c) The radius of a metal atom is taken as half the nearest metal-metal distance in a metallic crystal. (d) One tetrahedral void per atom is present in hcp structure. Question Type C : Comprehention Based Questions Conjugation occurs when there is alternative double and single bond like 1, 3-butadiene other type of delocalisation is  - bond, -lone pair and -vaccant orbital. As the number of resonanting structure increases, stability of system also increases. In any organic reactions as the stability of intermediate species increases reactivity of initial compound increases by process of neutralisation.31. Which of the following anion is most stable due to delocalisation?
32. What are the stability order of the following intermediates? 
33. Which of the following ion is most stable ?
When halogenation of alkenes occur, intermediate formation of cyclic halonium takes place by ionic mechanism. When cyclopentene reacts with bromine in presence of CCl4 anti addition occurs and gives trans isomer so addition of halogen to an alkene is a stereospecific reaction.
Intermediate forms are
35. Trans-2-butene on reacting with Br2 in CCl4 forms mainly
38. Which ether cannot prepared by willamson’s syntheris
39. When ROH reacts with SOCl2 and no added base, which is correct statement for reaction (a) Retention of configuration occurs (b) This is an example of SNi mechanism (c) The Cl of the anion of the ion pair attacks the front side of the C+, with retention of configuration (d) In this reaction if weakbase pyridine is present inversion of configuration occurs. Athletes sometimes upset the buffering of their blood through a process called hyperventilation. In the excitement and anxiety of a contenst, they breathe more rapidly and deeply they need to. When hyperventilation occurs, a person expels more CO2 than necessary, upsetting the carbonic acid equilibrium. According to Le-Chateliers principle, as the CO2 is exhaled, more H2CO3 decomposes to replace the CO2 in the reaction :  As H2CO3 is used, the equilibrium between carbonic acid and hydrogen carbonate is upset and HCO3– is consumed in replacing the H2CO3.  Eventually, the HCO3– concentration drops to the point at which it is insufficient to maintain the blood pH at a safe level. Because using HCO3–, also consumes H3O+, the blood pH is raised (becmes more basic). One response of the body to this condition is a construction of the cerebral blood vessels. As the blood flow to the brain is reduced, the individual becomes dizzy and can lapse into unconciousness. At that point, the body’s reflex mechanisms usually restore normal breathing and the blood pH returns to normal. 40. To maintain a pH of 7.4 for blood at normal condition which is 2 M in H2CO3 (at equilibrium). What volume of 5 M NaHCO3 solution is required to mix with 10 mL of blood?
41. The administration of medicine containing H2PO4– in significant amount will :
42. Dizziness of athlete is caused basically due to increased :
The amount of sulphur present in steel samples can be determined by conversion of the sulphur to hydrogen sulphide which is subsequently estimated by titration with iodine. In this latter process the H2S is converted to elemental and the iodine reduced to iodide ion. Iodine solutions used in volumetric analysis is standardised prior to use as iodine is volatile and the solutions decrease in concentration with storage. One way of standardising iodine solutions is by titrating against a known mass of arsenic (III) oxide. One representation of this reaction is as follows:  43. In the standardisation method essentially sodium hydrogen carbonate is added in excess to the solution of arsenic (III) oxide is : (a) the impurity of iodine gets precipitated out with Na (b) NaHCO3 combines with H+ drives equilibrium completely in forward direction (c) NaHCO3 drives the equilibrium backward releasing H+, thus maintains pure iodine (d) NaHCO3 produces NaI and thus prevents the volatility. 44. During volumertric analysis chemist finds that the H2S liberated from a 5.00 g sample of steel requires 1.90 mL of 0.049 M iodine solution to reach an end point in the titration. The percentage of sulphur in the steel sample is :
(i) A white amorphous powder (A) on heating strongly gives a colourless non-combustible gas (B) and solid (C). (ii) The gas (B) turns lime water milky and turbidity disappears with the passage of excess of gas. (iii) The solution of (C) in dilute HCl, (D), gives a white precipitate with aqueous solution of K4Fe(CN)6. (iv) (D) gives a white precipitate (E) on passing H2S in presence of excess of NH4OH. 45. Compound (A) (white amorphous powder) is
46. Gas (B) which turns lime water milky is
47. Compound (D) is
Question type D : Column Matching Type Questions
The matching grid :
49. Following formation reactions are given at 25°C. Match the column I with the appropriate defect in formation equation
The matching grid :
50. Match the column (I) & (II) such that the options from table II can satisfies table (I)
The matching grid :
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The product obtain in the reaction is
Final product is
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