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Q. No. 3 Which of the following has the highest normal boiling point? Option 1 Iodobenzene Option 2 Bromobenzene Option 3 Chlorobenzene Option 4 Fluorobenzene Correct Answer 1 Explanation As the size of the halogen atom increase van der waal forces increases, boiling point increases. Size of the halogen mass density. Q. No. 4 Which of the following are arranged in the decreasing order of dipole moment? Option 1 CH3 Cl,CH 3 Br,CH 3 F Option 2 CH3 Cl,CH 3 F,CH 3 Br Option 3 CH3 Br,CH 3 Cl,CH 3 F Option 4 CH3 Br,CH 3 F,CH 3 Cl Correct Answer 2 Explanation acc to EN of R­F> R­Cl . But due to the small size. F ­ ion cannot accommodate the ­ ve charge. So less polar they R ­ Cl . Q. No. 5 Assertion : The carbon halogen bond in an aryl halid e is shorter than the carbon halogen bond in all alkyl halide. Reason : A bond formed of an sp 3 orbital should be shorter than the corresponding bond involving an sp 2 orbital. Option 1 If both assertion and reason are correct and reason is the correct explanation of assertion. Option 2 If both assertion and reason are true but reason is not the correct explanation of assertion. Option 3 If assertion is true but assertion is false. Option 4 If reason is true but assertion is false. Correct Answer 3 Explanation bond of aryl halide is shorter than the C ­ X bond of an alkyl halide, due to the +M effect of ­X which forms a partial double bond. Q. No. 7 Assertion : Alkyl iodide can be prepared by treating alkyl chloride/bromide with NaI in acetone. Reason : NaCI/NaBr are soluble in acetone while NaI is not. Option 1 If both assertion and reason are correct and reason is the correct explanation of assertion. Option 2 If both assertion and reason are true but reason is not the correct explanation of assertion. Option 3 If assertion is true but assertion is false. Option 4 If reason is true but assertion is false. Correct Answer 3 Explanation NaCl/NaBr (ionic) are insoluble in (non corlless polar). Q. No. 8 The number of possible enantiomeric pairs that can be produced during monochlorination of 2­methyl butane is : Option 1 3 Option 2 4 Option 3 2 Option 4 1 Correct Answer 3 Explanation i and iii having a chiral carbon (*), each chiral molecular can produce a pair of enantiomers (R and S). Q. No. 9 Option 1 Option 2 Option 3 Option 4 Correct Answer 2 Explanation Anti addition. Passage Text Addition of X 2 on alkene is electrophilic addition reaction. Reaction proceed through the formation of 3­membered cyclic halonium ion. Nucleophile X ­ attacks from backside of cyclic halonium ion hence total reaction is anti addition reaction. If this reaction proceed in polar solvent then solvent itself acts as nucleophile. Mechanism : Q. No. 1 0 Which of the following statements is incorrect? Option 1 Symmetrical trans alkene gives 2 products on reaction with Br 2/CCl 4 Option 2 Symmetrical cis alkene gives 2 product on reaction with Br 2/CCl 4 Option 3 Trans alkenes give erythro product Option 4 Cis alkenes gives thero product Correct Answer 3 Explanation cis­ Antiaddition racemic trans­ Antiaddition meso TAM Q. No. 1 1 Option 1 Option 2 Option 3 Option 4 Correct Answer 2 Explanation More substituted alkene is mo re reactive. Q. No. 1 2 Option 1 Option 2 Option 3 Option 4 Correct Answer 4 Explanation Addition of X 2 to an alkene in electrophilic add ition (Anti), if polar solvent is taken, solvent itself acts as a nucleophile. Q. No. 1 3 How many of the following reaction, leads to the formation of diastereomers. Correct Answer b, d, e, f. Is Integer Type ☒ Explanation Products of those runs will have two chiral centres. An org. compounds should have at least two chiral centres to produce diasteromers. Q. No. 1 4 When but ­3­en ­ol reacts with aq. HBr, the product formed is Option 1 3 ­ bromobut ­ 1 ­ ene Option 2 1 ­ bromobut ­ 2 ­ ene Option 3 A mixture of both a and b Option 4 2 ­ bromobut ­ 2 ­ ene Correct Answer 3 Explanation Q. No. 1 5 Match the Following No. Column A Column B Column C Id of Additional Answer 1 HBr.RCOOR Anti ­ CH3 CH= CH 2 Markovnikov’s addition 2 HBr Markovnikov’s CH3 CH= CH 2 addition 3 NBS,hv Side chain C6 H 5 CH 3 substitution 4 Br/FeBr 3 Aromatic C6 H 5 CH 3 substitution Explanation Go through the hydrocarbon’s properties. Q. No. 1 6 Which of the following reactions involve free radical as intermediate? Option 1 ☐ Option 2 ☒ Option 3 ☒ Option 4 ☒ Explanation a ­ Aromic electrophilic substitution. Q. No. 1 7 Assertion : Chlorination of Allylic hydrogen is difficult than vinylic hydrogen. Reason : Allyl radical is stabilized by resonance. Option 1 If both assertion and reason are correct and reason is the correct explanation of assertion. Option 2 If both assertion and reason are true but reason is not the correct explanation of assertion. Option 3 If assertion is true but assertion is false. Option 4 If reason is true but assertion is false. Correct Answer 4 Explanation Chlorination of Allylic hydrogen is easy as it form allyl radica l (more ­ stable) Q. No. 1 8 Acetone Assertion : CH32 ­ CH ­ Cl+ NaI CH 32 ­ CH ­ I+ NaCl Reason : Acetone is polar protic solvent and solubility order of sodium halides decreases dramatically in order NaI > NaBr > NaCl . The last being virtually insoluble in this solvent and a 1 0 and 2 0 chloro alkane in acetone is completely driven to the side of Iodoalkane by the precipitation. Option 1 If both assertion and reason are correct and reason is the correct explanation of assertion. Option 2 If both assertion an d reason are true but reason is not the correct explanation of assertion. Option 3 If assertion is true but assertion is false. Option 4 If reason is true but assertion is false. Correct Answer 3 Explanation Q. No. 1 9 Option 1 Option 2 Option 3 Option 4 Correct Answer 1 Explanation Form through benyl C""" . Q. No. 20 Stereochemistry of the product are : Option 1 Diastereomers Option 2 Meso Option 3 Racemic mixture Option 4 Pure enantiomers Correct Answer 3 Explanation cis+ transaddition Racemicmixture . Q. No. 21 An organic compound C 3H7Br(A) with alcoholic KOH forms C 3H6 which decolorizes Br 2 in CCl 4 but does not gives a white precipitate with ammonical AgNO 3. (A) on reaction with KCN forms a product which on reduction with Na/C 2H5OH produces n­butyl amine. Hence, the compound (A) is Option 1 n­propyl bromide Option 2 isopropyl bromide Option 3 1, 1 ­dibromopropane Option 4 none of these Correct Answer 1 Explan ation Follow retro synthesis Start with the final product It is an alkene, has no acidic ‘H’. Q. No. 22 A compound ‘A’ has molecular formula C 5H9Cl. It does not react with bromine in CCl 4. On treatment with strong base, it produces single ‘B’ (C 5H8) and reacts with Br 2(aq). Ozonolysis of ‘B’ produces a compound C 5H8O2. Which of the following is structure of A? Option 1 Option 2 Option 3 Option 4 Correct Answer 2 Explanation An unsaturated Alkyl halide, but do not react with Cl 2 means, it is saturated compound isomers an Q. No. 23 Mark out the possible product. Option 1 ☒ Option 2 ☒ Option 3 ☐ Option 4 ☐ Explanation Ring expansion and direct substitution. Q. No. 24 Which of the following pair is correctly matched? Option 1 Reaction Product ☒ RX + AgCN RNC Option 2 RX + KCN RCN ☒ Option 3 RX + KNO 2 ☐ Option 4 RX + AgNO 2 R ­O­N=O ☐ Explanation Q. No. 25 Assertion : Treatment of chloromethane with a saturat ed solution of AgCN gives ethyl isocyanides as the major product. Reason : Cyanide (CN ­) is an ambident nucleophile. Option 1 If both assertion and reason are correct and reason is the correct explanation of assertion. Option 2 If both asse rtion and reason are true but reason is not the correct explanation of assertion. Option 3 If assertion is true but assertion is false. Option 4 If reason is true but assertion is false. Correct Answer 2 Explanation Correct reason for assertion: AgCN is a covalent compound in switch connecting atom is ‘N’ C N ­ . Q. No. 26 Choose the correct statement(s) about the following reaction. I. The major product of the reaction is butyl­methyl ether. II. The major product of the reaction is 1­butene. III. The major product is formed by S reaction mechanism. N2 IV. The major product is followed by E2 reaction mechanism. Option 1 I + III Option 2 II + IV Option 3 I + IV Option 4 IV Correct Answer 1 Explanation Q. No. 27 The major substitution product of the following reaction is Option 1 Option 2 Option 3 Option 4 Correct Answer 4 Explanation S ­ inversion of configuration. N2 Q. No. 28 Consider the following reaction X and Y are respectively Option 1 Both nitroethane Option 2 Both ethyl nitrite ( EtONO Option 3 X = EtONO and Y = EtNO 2 Option 4 X = EtNO 2 and Y = EtONON Correct Answer 3 Explanation Q. No. 29 Alkyl halides react with dialkyl copper reagents to give Option 1 Alkenes Option 2 Alkyl copper halides Option 3 Alkanes Option 4 Alkenyl Halides Correct Answer 3 Explanation Corey ­ House synthesis.

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