1. The rate of a reaction is expressed in different ways as follows:

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1 1. The rate of a reaction is expressed in different ways as follows: The reaction is: (A) 4 A + B 2C + 3D (C) A + B C + D (B) B + 3 D 4 A + 2 C (D) B + D A + C 2. The reactions of higher order are rare because (A) many body collisions involve very high activation energy (B) many body collisions have a very low probability (C) many body collisions are not energetically favoured. (D) many body collisions can take place only in the gaseous phase. 3. Consider the following first order competing reactions: if 50% of the reaction of X was completed when 96% of the reaction of Y was completed, the ratio of their rate constants (k 2 /k 1 ) is Ans: D (A) 4.06 (B) (C) 1.1 (D) A first order reaction is 50% completed in 20 minutes at 27 C and in 5 min at 47 C. The energy of activation of the reaction is (A) kj/mol (B) kj/mol (C) kj/mol (D) 6.65 kj/mol 5. The following mechanism has been proposed for the exothermic catalyzed complex reaction. If k 1 is much smaller than k 2. The most suitable qualitative plot of potential energy (P.E.) (Y-axis) versus reaction co-ordinate (x-axis) for the above reaction.

2 Read the passage for the following questions (6 & 7): Oxidation of metals is generally a slow electrochemical reaction involving many steps. These steps involve electron transfer reactions. A particular type of oxidation involve overall first order kinetics with respect to fraction of unoxidised metal (1 f ) surface thickness relative to maximum thickness (T) of oxidised surface, when metal surface is exposed to air for considerable period of time 6. The time taken for thickness to grow 50% of 'T' is (A) 23.1 hrs (B) 46.2 hrs (C) 100 hrs (D) 92.4 hrs 7. The exponential variation of 'f' with t(hrs) is given by Ans: A 8. Give the correct order of initials T (true) or F (false) for following statements. (i) On bombarding 7 N 14 Nuclei with -particle, the nuclei of the product formed after release of proton would be 8 O 17. (ii) 89 Ac228 and 90 Th 229 belong respectively to Actinium and Neptunium series.

Ans: A (iii) Nuclide and it's decay product after -emission are called isodiaphers. (iv) Half life of radium is 1580 years. Its average life will be 1097.22 years.

3 Ans: A (iii) Nuclide and it's decay product after -emission are called isodiaphers. (iv) Half life of radium is 1580 years. Its average life will be years. (A) TFTF (B) TTTF (C) FFTT (D) TFFF 9. One difference between first and second-order reactions is that: A. the rate of both first-order and second-order reactions does not depend on reaction concentrations B. the half-life of a first-order reaction does not depend on [A] 0 ; the half-life of a second-order reaction does depend on [A] 0 C. a first-order reaction can be catalyzed; a second-order reaction cannot be catalyzed D. the rate of a first-order reaction depends on reaction concentrations; the rate of a second-order reaction does not depend on reactant concentrations Read the comprehension below to answer questions10 to 14: 10. Which is the faster step in the forward direction? (A) (B) (C) (D) Data insufficient 11. Which is the faster step in the backward direction? (A) (B) (C) (D) Data insufficient 12. Which is the fastest step among the six steps? (A) (B) (C) (D) 13. Which is the rate determining step in the forward direction? (A) (B) (C) (D) Can t be predicted 14. Which is the rate determining step in the forward direction? (A) (B) (C) (D) Can t be predicted

15. For the reaction, the following mechanism has been suggested:.. Eqb. onstant.. Rate determining step.. Fast What is the overall order of the reaction? (A) Zero (B) 1 (C) 2 (D) 3 16.

4 15. For the reaction, the following mechanism has been suggested:.. Eqb. onstant.. Rate determining step.. Fast What is the overall order of the reaction? (A) Zero (B) 1 (C) 2 (D) A reaction takes place by the following mechanism Transition state(s) are shown by: (a) III, V (b) II, IV (c) II, III, IV (d) III only 17. The product (B) in the following reaction is Acetamide P2O H A 4 B 5 (A) CH 3NH 2 (B) C 2H 5NH 2 (C) CH 3CN (D) CH 3COONH 4 B 18. Which of the following will give a positive carbylamine test 1. H 3 CNH 2 2. CH 3 NHCH 3 3. (CH 3 ) 3 N 4. C 6 H 5 NH 2 (A) 1 and 3 (B) 2 and 4 (C) 3 and 4 (D) 1 and 4 D

5 19. Which of the reagent is not used to convert nitrobenzene to aniline (A) H 2 /Ni (B) Sn+HCl (C) SnCl 2 in HCl (D) LiAlH 4 D 20. Which of the following is weakest base in water (A) Aniline (C) Trimethylaniline (B) p-nitoroaniline (D) ammonia B 21. Towards electrophilic substitution, the most reactive species be (A) NO 2 (B) NH 2 (C) NH 3 Cl (D) NHCOCH For selective reduction of m-dinitrobenzene to m- nitroaniline, the reducing agent is (A) Sn/HCl (C) (NH 4 ) 2 S (B) Zn/NH 4 Cl(aq) (D) alkaline solution of glucose Ans: (C) 23. The conjugate acid of HO(CH 2 ) 3 NH 2 is (A) H 2 O + (CH 2 ) 3 NH 2 (B) HO(CH 2 ) 3 N H3 (C) O (CH2 ) 3NH 2 (D) HO(CH 2 ) 3 H 24. Identify (Z) N C 6 H 5 COOH 1.LiAlH4 (X) (Y) (Z) 2.PBr3 KCN LiAlH 4 (A) C 6 H 5 CH 2 NH 2 (B) C 6 H 5 CH 2 CH 2 NH 2 (C) C 6 H 5 CH 2 CH 2 CH 2 NH 2 (D) C H 6 5 CH NH 2 I CH 3

6 25. When aniline is treated with bromine water it forms (A) 2 bromoamiline (C) mixture of 2 and 4 bromoaniline (B) 4-bromoaniline (D) 2,4,6 -tribromoaniline Ans: D 26. Match the compounds (in aqueous medium) in column 1 with their nature in column 2 Column 1 Column 2 I. Acetamide a. Acidic II. Benzonitrile b. Basic III. Triethylamine c. neutral IV. Phenol (a) I c, II c, III b, IV a (b) I b, II c, III c, IV a (c) I c, II b, III b, IV b (d) I a, II a, III c, IV b Ans: (A) 27. x and y reagents are Ans: (C) 28. Ans: D The question below (29-30) consists of an Assertion in column 1 and the Reason in column 2. Use the following key to choose the appropriate answer. (a) If both assertion and reason are correct, and reason is the correct explanation of the assertion (b) If both assertion and reason are correct, but reason is not correct explanation of the assertion. (c) If assertion is correct, but reason is Incorrect. (d) If assertion is Incorrect, but reason is correct. 29. Assertion: Nitration of benzene is an electrophillic substitution reaction Reason: Nitration of C6H6 and C 6 D 6, using nitrating mixture takes place at the same rate.

7 30. Assertion: Acylation of aniline increases the reactivity of benzene ring Reason: Acylation of aniline results in decrease of electron density at the benzene ring Ans: (D)

COMPOUND CONTAINING NITROGEN. 1) Which will give nitrosoamine when treated with?

COMPOUND CONTAINING NITROGEN. 1) Which will give nitrosoamine when treated with? COMPOUND CONTAINING NITROGEN 1) Which will give nitrosoamine when treated with? C 6 H 5 NHCH 3 b) H 3 C NH H 3 C H N d) All of these 2) What is the end product in following sequence of reactions? C 2 H