1. aipmt–Past papers CHEMISTRY- UNSOLVED PAPER - 2008

2. SECTION – I (Total Marks : 50) Single Correct Answer Type There are five parts in this question. Four choices are given for each part and one of them is correct. Indicate you choice of the correct answer for each part in your answer-book by writing the letter (a), (b), (c) or (d) whichever is appropriate

3. 01 Problem Which one of the following arrangements does not give the correct picture of the tends indicated against it? a. b. c. d.

4. Problem 02 If a gas expand at a constant temperature, it indicate that Kinetic energy of molecule remain the same Number of molecule of gas increase Kinetic energy of molecule decrease Pressure of the gas increase

5. Problem 03 The dissociation equilibrium of a gas AB2 can be represented as: The degree of dissociation is x & is smaller compared to 1. The expression to 1. The expressing relating the degree of dissociation (x) with equilibrium constant & total pressure P is a. b. c. d.

6. Problem 04 The bromination of acetone that occurs in acid solution is represented by this equation These kinetic data were obtained for given reaction concentration. Initial concentration, M Initial rate, disappearance of Initial rate, disappearance of a. b. c. d.

7. Problem Based on these data, the rate equation is a. b. c. d.

8. Problem 05 If the concentration of OH- ions in the reaction Is decreased by 1/4times, then equilibrium concentration of will increased by 64 times times 8 times 16 times

9. Problem 06 What volume of measured at & 1 atm, is needed to burn completely 1L of propane gas measured under the same conditions? 5L 10L 7L 6L

10. Problem 07 Equal volume of three acids solutions of pH 3, 4 & 5 are mixed in a vessel. What will be the ion concentration in the mixture? a. b. c. d.

11. Problem 08 The relative reactivities of acyl compounds towards nucleophilic substitution are in the order of Acid anhydrite > Amide >Ester > Acyl chloride Acyl chloride > Ester > Acid anhydrite > Amide Acyl chloride > Acid anhydrite > Ester > Amide Ester > Acyl chloride > Amide> Acid anhydrite

12. Problem 09 In DNA, the complimentary bases are Adenine & Guanine; thymine & Cytosine Uracil & Adenine; Cytosine & Guanine Adenine & thymine; Guanine & Cytosine Adenine & thymine; Guanine & Uracil

13. Problem 10 Base strength of is in order of (i)> (iii)> (ii) (i)> (ii) > (iii) (i)> (i)> (iii) (iii)> (ii) > (i)

14. Problem 11 Equimolar solution of the following were prepare in water separately. Which one of the solution will record the highest pH? a. b. c. d.

15. Problem 12 The sequence of ionic mobility in aqueous solution is a. b. c. d.

16. Problem 13 If uncertainty in position & momentum are equal, then uncertainty in velocity is a. b. c. d.

17. Problem 14 How many stereoisomer’s does this molecule have? CH3CH=CHCH2CHBrCH3 8 2 4 6

18. Problem 15 On the basis of the following values, the shortest oxidizing agent is a. b. c. d.

19. Problem 16 The correct order of decreasing second ionization enthalpy of Ti (22), V (23), Cr (24) & Mn (25) is Mn > Cr> Ti>V Ti > V > Cr > Mn Cr > Mn > V > Ti V > Mn > Cr > Ti

20. Problem 17 Which one of the following is most reactive towards electrophilic attack ? a. b. c. d.

21. Problem 18 Four diatomic species are listed below in different sequences. Which of these presence the correct order of there increasing bond order? a. b. c. d.

22. Problem 19 How many moles of lead (II) chloride will be formed from a reaction between 6.5g of PbO & 3.2b HCl ? 0.011 0.029 0.044 0.333

23. Problem 20 The stability of carbanions in the followings is in the order of (i) RC = C (ii) R2C = CH (iii) (iv) R3C - CH2 (iv)> (ii)>(iii)>(i) >(iii) > (ii)> (iv) > (ii)> (iii) >(iv) (ii)> (iii) >(iv)> (i)

24. Problem 21 Acetophenone when reacted with a base, , yields stable compound which has the structure a. b. c. d.

25. Problem 22 Volume occupied by 1 molecule of water (density= 1g ) is a. b. c. d.

26. Problem 23 Bond dissociation enthalpy of are 434,242 & 431 respectably. Enthalpy of formation HCl is a. b. c. d.

27. Problem 24 Which of the following complexes exhibits the highest paramagnetic behavior ? a. b. c. d.

28. Problem 25 Which one of the following statement is not true? Buna-S is a copolymer of butadiene & styrene. Natural rubber is a 1, 4-polymer of isoprene. In vulcanization, the formation of sulphur bridges between different chains make rubber harder & stronger. Natural rubber has the trans-configuration at every double bond.

29. Problem 26 In a reaction of aniline a coloured product C was obtained The structure of C would be a. b. c. d.

30. Problem 27 Which of the following condition are correct? a. b. c. d.

31. Problem 28 The measurement of the electron position is associated with an uncertainty in momentum, which is equal to . The uncertainty in electron velocity is (mass of an electron is ). a. b. c. d.

32. Problem 29 The angular shape of ozone molecule consists of a. b. c. d.

33. Problem 30 Percentage of free space in a body centered cubic units cell is 34% 28% 30% 32%

34. Problem 31 The value of equilibrium constant of the reaction Is 8.0. the equilibrium constant of the reaction will be 16 1/8 1/16 1/64

35. Problem 32 The values of Kp1 & Kp2 for the reaction Are in the ratio 9:1. If degree of dissociation of X & A be equal, the total pressure at equilibrium (i) & (ii) are in the ratio 36:1 1:1 3:1 1:9

36. Problem 33 Are in the ratio 9:1. If degree of dissociation of X & A be equal, the total pressure at equilibrium (i) & (ii) are in the ratio 36:1 1:1 3:1 1:9

37. Problem 34 Which of the following is an amine hormone? Insulin Progesterone Thyroxine Oxypurin

38. Problem 35 Kohilrausch’s laws states that at Infinity dilution, each ion makes definite contribution to conductance of an electrolyte what ever be the nature of the other ion of the electrolyte. Infinity dilution, each ion makes definite contribution to equivalent conductance of an electrolyte what ever be the nature of the other ion of the electrolyte. Finite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte what ever be the nature of the other ion of the electrolyte. Infinity dilution, each ion makes definite contribution to equivalent conductance of an electrolyte depending on the nature of the other ion of the electrolyte.

39. Problem 36 Green chemistry means such reaction which Are related to the depletion of ozone layer Study the reaction in plants Produce colour during reactions Reduce the use and production of hazardous chemicals

40. Problem 37 Which of the following question is not correct? The number of carbon atoms in a unit cell of diamond is 4. The number of bravaislattics in which a crystal can be categorize is 14 The fraction of the total volume occupied by the atoms in a primitive cell is 0.48 Molecular solids are generally volatile.

41. Problem 38 In a substitution reaction of the type Which one of the following has the highest relative rate? a. b. c. d.

42. Problem 39 The correct order of increasing bond angle in the following triatomic species is a. b. c. d.

43. Problem 40 With which one of the following elements silicon should be doped so as to give p-type of semiconductor ? Selenium Boron Germanium Arsenic

44. Problem 41 A (predominantly) is a. b. c. d.

45. Problem 42 An organic compound contains C, H & O. its elemental analysis gave C, 38.71% & H, 9.67%. The empirical formula of the compound would be a.CHO b. c. d.

46. Problem 43 In which of the following coordination entities the magnitude of (CFSE is octahedral field) will be maximum? a. b. c. d.

47. Problem 44 The alkali metals from salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orders? NaH > LiH >KH > RbH > CsH LiH > NaH > KH > RbH > CsH CsH > RbH > KH > NaH > LiH KH > NaH > LiH > CsH > RbH

48. Problem 45 Which of the following are not state function? (i)q+w (ii)q (iii)w (iv)H-TS i), (ii) & (iii) & (iii) & (vi) (ii), (iii) & (vi)

49. Problem 46 In the hydrocarbon, The state of hybridization of carbon 1, 3 & 5 are in the following sequence a. b. c. d.

50. Problem 47 Number of moles of required to oxidize one mole of ferrous oxalate completely in acidic medium will be 7.5moles 0.2 moles 0.6 moles 0.4 moles

51. Problem 48 The rate constants for two different reactions are , respectively. The temperature at which is 2000 K 1000/2.303K 1000K 2000/2.303K

52. Problem 49 A strong base can abstract an α-hydrogen from Keton Alkane Alkene Amine

53. Problem 50 Standard free energies of formation (in kJ/mol) at 298K are -237.2, -394.4 & -8.2 for respectively. The value of for the pentane – oxygen fuel cell is 1.0968 V 0.0968V 1.968V 2.0968V

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