C 3 H 6 ClBr represent a saturated alkyl halide. The following structural isomers are possible for the given compound. Among the above 5 structural is

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1 Q. No. 1 In CH 3 CH 2 Br, % of Br is Molecular mass of CH 3 CH 2 Br = 109 At Wt. of Br = % of Br is = 100 = Q. No. 2 Which of the following is primary halide Isopropyl iodide Secondary butyl iodide Tertiary butyl bromide Neo hexyl chloride Correct Answer 4 In Neo hexyl chloride Cl is attached to 1 0 carbon. Q. No. 3 Among these compounds, which one has shortest C Cl bond? I II III IV In Chlorine is directly attached to an sp 2 carbon. Q. No. 4 How many structural isomers of C 3 H 6 ClBr are possible and how many of them are optically active respectively? 5, 2 5, 3 4, 2 3, 2

2 C 3 H 6 ClBr represent a saturated alkyl halide. The following structural isomers are possible for the given compound. Among the above 5 structural isomers i, ii, iii are optically active since they have chiral centre. Q. No. 5 Correct order of B.P. for the alkyl halide is C2H5Cl > C2H5Br > C2H5I C2H5I > C2H5Br > C2H5Cl C2H5I > C2H5Cl > C2H5Br C2H5Br > C2H5I > C2H5Cl For the same alkyl gp : B.P of alkyl halide increases with the size of the halogen atom C H I > C H Br > C H Cl Q. No. 6 The following reaction is known as Pyridine C H OH + SOCl C H Cl + SO + HCl Kharasch effect Darzen s procedure Williamson s synthesis Hunsdiecker synthesis reaction The reaction is Darzen s process. In the presence of pyridine in this invesion of configuration occurs (SN 2 ). Q. No. 7 CS Silver acetate + Br 2 2. The main product of this reaction is CH3 Br CH 3 COI CH 3 COOH None of these

3 Borodine Huncdiecker reaction. Q. No. 8 Preparation of alkyl halides in laboratory is least preferred by Treatment of alcohols Addition of hydrogen halides to alkenes Halide exchange Direct halogenation of alkanes Correct Answer 4 Direct halogenation alkenes yellows free radical mechanism. There also forms biproducts which decreases the yield of desired product and separation is difficult. Ex: CH + Cl ml 4 2 CH3Cl + HCl + CH2Cl 2 + CHCl 3 + CCl4 Q. No. 9 Which of the following organic compounds will give a mixture of 1 chlorobutane and 2 chlorobutane on hydro chlorination (HCl) Correct Answer 4 Q. No. 10 Decreasing order of reactivity of HX in the reaction ROH + HX RX + H2O HI > HBr > HCl > HF HBr > HCl > HI > HF HCl> HBr > HI > HF HF > HBr > HCl> HI In the given reaction alcohol to be protonated first HI being a strong acid among the given hydrogen halides, readily gives the proton. The order is : HI> HBr > HCl > HF Q. No. 11 Light C2H 8 + Cl2 C3H7Cl + HCl Is an example of which of the following types of reactions Substitution Elimination

4 Addition Rearrangement The given reaction is an example for the halogenation of alkane, which proceeds through free radical substitution Meehan. Q. No. 12 What will be the product in the following reaction NBS (N Bromosuccihamide) substitute at Allylic position Allylic bromination takes place Q. No. 13 2, 6 Dimethyl heptane on monochlorination produces. derivatives

5 iii and iv are chiral, hence they can produce 2 isomers each (R & S), Total isomers = 6 Q. No. 14 Which of the following reagents could be used to convert cyclohexanol to chlorocyclohexane? Cl 2, light SOCl 2 PBr 3 None of these It is an SN 1 type reaction. Q. No. 15 The reaction Proceed by the mechanism : S N 1 S N 2 S E S N 1 Darzen s process Q. No. 16 Vinyl chloride reacts with HCl to form 1, 1 dichloro ethane 1, 2 dichloro ethane Tetrachloro ethylene Mixture of 1, 2 and 1, 1 dichloro ethane

6 Q. No. 17 Obtained by chlorination of n butane will be: Meso form Racemic mixture d form l form Q. No. 18 Analyze the following reaction and identify the nature of A and B Correct Answer 3

7 Q. No. 19 (A) is: Correct Answer 4 Peroxide effect Br 0 goes to less substituted carbon in an unsymmetrical alkene. Q. No. 20 In the following reaction find the correct product:

8 Correct Answer 3 Finkel stein reaction involves in the preparation of alkyl iodides from remaining alkyl halides. Q. No. 21 Formation of free radical takes place with absorption of minimum energy in the formation of : Correct Answer 4 Q. No. 22 When CH 3 CH 2 CHCl 2 is treated with NaNH 2 the product formed is CH 3 CH 2 CH(NH 2 )(Cl)

9 CH 3 CH 2 C(NH 2 ) 2 De hydro halogenation reaction elimination Q. No. 23 Ethyl bromide reacts with silver nitrite to form Nitro ethane Nitro ethane and ethyl nitrite Ethyl nitrite Ethane Q. No. 24 Which of the following are correct statements about C 2 H 5 Br It reacts with metallic Na to give ethane It gives Nitro ethane on heating with aqueous ethanolic solution of AgNO 2 It gives C 2 H 5 OH On boiling with alcoholic potash It forms ethyl acetate on heating with silver acetate a & c are wrong 1as it gives n butane with metallic Na (warts ran) and ethylene with Alc.KOH Q. No. 25 Ethylene dichloride and ethylidene chloride are isomeric compounds. The false statement about these isomers is that they React with alcoholic potash and give the same product Are position isomers Contain the same percentage of chlorine Are both hydrolyzed to the same product Correct Answer 4 Ethylene dichloride and ethylidene chloride are isomeric compounds. The false statement about these isomers is that they are both hydrolyzed to the same product. Q. No. 26 Bottles containing C 6 H 5 I and C 6 H 5 CH 2 I lost their original labels. They were labelled A and B for testing. A and B were separately taken in test tubes and boiled with NaOH solution. The end solution in each tube was made acidic with dilute. HNO 3 and then some AgNO 3 solution was added. Substance B give a yellow precipitate. Which one of the following statements is true for this experiment A was C 6 H 5 I A was C 6 H 5 CH 2 I B was C 6 H 5 I Addition of HNO 3 was unnecessary

10 Q. No. 27 What is the major product of the reaction? Correct Answer 3 Q. No. 28 Which of the following reaction is a good way to prepare methyl tert butyl ether? CH O Na+ (CH ) CBr (CH ) CO K + CH I NaOH (CH ) COH +CH OH CH MgBr + (CH ) COCI 3 3 3

11 Q. No. 29 The product B of the following sequence, would be I II III IV and V Hoffmann elimination Q. No. 30 Iodine from iodoethane can be substituted by cyanide group in a number of ways. Which of the following is true statement? With either KCN or AgCN, EtCN is formed as major product. With either KCN or AgCN, EtCN is formed as major product. With AgCN, EtCN and with KCN, EtNC is formed. With AgCN, EtNC while with KCN, EtCN is formed as major product. Correct Answer 4 Agn covalent connecting atom is N ETNC Q. No. 31 What is the product of the following reaction?

12 Both (a) and (b) Neither (a) nor (b) Correct Answer 4 The reaction follows SN 2 (inversion) Q. No. 32 To make this ether which of the following reaction will be most suitable? Both (a) and (b) Correct Answer 4 In both the options one of the reactants in phenoxide ion (stable) and in other reactants have good leaving groups. Q. No. 33 Aq KCN CH CH CH I P EtOH Major

13 P should be CH CH CH CN CH CH = CH 3 2 Both (a) and (b) in equal proportions None of these Aq.KCN Substitution takes place alkyl nitrile formed, since KCN is ionic. Q. No. 34 CH CH NH + CH I P Excess P should be CH3 CH2 NH CH3 Major CH CH N CH CH 2= CH2 Correct Answer I Q. No. 35 Bothe (a) and (b) in equal proportions None of these The reaction is Nucleophilic substitution followed by hydrolysis and esterification. Product is an ester.

14 Q. No. 36 P should be Both of these in equal proportions None of these Q. No. 37 An alkyl bromide (X) reacts with Na to form 4, 5 diethyl octane. Compound X is CH 3 (CH 2 ) 3 Br CH 3 (CH 2 ) 5 Br CH CH CH Br CH CH CH CH Br CH CH Correct Answer

15 Q. No. 38 Deduce the structure of A : Correct Answer 3 Q. No. 39 Which of the following cannot be obtained as the only product in the wurtz s coupling reaction of halides with sodium metal in ether solution? a, d are unsymmetrical (odd no. of. Carbons) since the wurtz reaction is to proper the symmetrical alkanes (even no. of. Carbons). Q. No. 40 Corey house synthesis is a much more convenient method for making alkanes for which of the following reasons?

16 Two different alkyl halides can be use. From one alkyl halide, R 2 CuLi is prepared and then this is reacted with another alkyl halide The reagent R 2 CuLi can be prepared from 1 0, 2 0 or 3 0 alkyl halide as well as from halo benzene Both (a) and (b) None of these Correct Answer 3 It is to prepare odd no. alkanes. Q. No. 41 Which of the following combinations of reactant is better for making propane? CH CuLi + CH CH Br CH CH CH Et CuLi + CH Br CH CH CH Both of these None of these Smaller R X are preferred in Corey House synthesis. Q. No. 42 Which of the following combinations of reactant is better for making neopentane? Both (a) and (b) None of these Smaller R X are preferred in Corey House synthesis. Q. No. 43 Na CH CH CH Br + CH CH Br P P is : P is mixture of three alkanes (n hexane, n butane and, pentane); none is formed in good yield P is a mixture of only two alkanes (n hexane and n butane); both are formed in good yield Both (a) and (b) depending upon other conditions None of these If different R X taken in wurtz reaction 3 types of alkanes will obtain. ether Q. No. 44 The addition of the Grignard reagent, CH 3 MgBr to acetaldehyde is a Nucleophilic addition to the carbonyl group. The Nucleophilic in this reaction is

17 CH3CHO CH 3 Br CH3 Correct Answer 4 Grignard reagent is a neutral Q. No. 45 H O 3 Ester A C4H8O 2 + CH3MgBr C4H10O (2 parts) (Alcohol B) Alcohol B reacts fastest with Lucas reagent. Hence A and B are : 2 moles of CH 3 Mg Br adding to the given ester and product is having a carbons i.e., alkane ate should have two carbons

18 Q. No. 46 3CH C H O CO 3MgBr H O A. A is 3 (C 2 H 5 O) 2 CHOH (CH 3 ) 3 COH (CH 3 ) 2 CHOH 2 moles of CH 3 Mg Br adding to the given ester and product is having a carbons i.e., alkane ate should have two carbons Q. No. 47

19 Q. No. 48 Correct Answer 4 Give iodoform test The product A formed can Further react with CH3MgBr/H3 O to give t butyl alcohols Be obtained by the ozonolysis of 2, 3 dimethyl 2 butane All are correct

20 2, 3 dimethyl 2 butane. Q. No. 49 Alkyl halides react with Mg in dry ether to form Magnesium halides Grignard s reagent Alkane Alkyne Q. No. 50 When phenyl magnesium bromides reacts with t butanol, the product would be Benzene Phenol t butyl benzene t butyl phenyl ether Grignard reagent abstracts proton from the compounds which have at least 1 acidic H Q. No. 51 Which of the following compounds is not suitable solvent for Grignard reagent?

21 Correct Answer 3 Ether is used as solvent in Grignard s reagent. Q. No. 52 product (X) is : Correct Answer 3

22 Q. No. 53 In the given reaction Find the product of reaction Correct Answer 3 Q. No. 54 P should be Both (a) and (b) None of these

23 Q. No. 55 The two optical isomers given below, namely Enantiomers Geometrical isomers Structural isomers Diastereomers Correct Answer 4 Non superimposable and non mirror images Diastereomers. Q. No. 56 Number of stereoisomers of the compounds, 2 chloro 4 methyl hex 2 ene is Q. No. 57 The number of enantiomers of the compound CH 3 CHBrCOOH is 1

24 2 3 4 Correct Answer 4 Q. No. 58 In the above process product A is Fluor benzene Benzene 1, 4 difluorobenzene 1, 3 difluorobenzene Q. No. 59 C 6 H 5 Cl prepared by aniline with HCl Cu 2 Cl 2 Cl 2 in presence of anhydrous AlCl 3 HNO 2 and then heated with Cu 2 Cl 2

25 Correct Answer 4 Q. No. 60 The following transformation proceeds through Benzene intermediate Oxirane Electrophilic addition Nucleophilic aromatic substitution Correct Answer 4 Aryl halides participate in Nucleophilic substation, if the benzene ring have electron with drawing groups. Aromatic Nucleophile substitution. Q. No. 61 This reaction follows S N 1 pathway S N 2 pathway Addition elimination pathway None of these Correct Answer 3 Aryl halide with electron with drawing group involves in Nucleophilic substitution Aromatic through addition elimination pathway.

26 Q. No. 62 In addition elimination pathway of nucleophilic aromatic substitution, which of the following compounds is most reactive? Reactivity : F > Cl > Br > I on benzene ring. I effect applied. Q. No. 63 In addition elimination pathway of Nucleophilic aromatic substitution, which of the following compounds is most reactive?

27 Correct Answer 3 Reactivity of halo arene no. of. Electron with drawing gaps on benzene ring. Q. No. 64 In addition elimination pathway of Nucleophilic aromatic substitutions, a NO 2 group is o, p directing and activating o, p directing and deactivating m directing and activating m directing and deactivating NO 2 gp directs the incoming nucleophile to O and P positions through M effect. faculties Nu

28 Q. No. 65 Based on the above reaction, the major product will Both in equal proportions None of these NO 2 gp directs the incoming nucleophile to O and P positions through M effect. faculties Nu Q. No. 66 Which of the following has the fastest rate of the reaction with NaCO 2 H 5? p fluoronitrobenzene p bromonitrobenzene p chloronitrobenzene p iodonitrobenzene I effect Q. No. 67 How many isomers are possible with trisubstituted benzene with all the three groups same?

29 Q. No. 68 Which of the following reaction is called Wurtz Fitting reaction? Both (b) and (c) Q. No. 69 Iodoform can be used as anesthetic Antiseptic Analgesic Antifebrin CHI 3 Iodoform. used as a wound powder. Q. No. 70 Which of the following is an anesthetic C 2 H 4 CHCl 3 CH 3 Cl C 2 H 5 OH

30 CHCl 3 (chloroform) used mild Anesthetic. Q. No. 71 An important insecticide is obtained by the action of chloral on chlorobenzene. It is BHC Gammexene DDT Lindane Correct Answer 3 Q. No. 73 DDT is prepared by reacting chlorobenzene with CCL 4 CCl3 CHO AgNO 3 solution Ethane Q. No. 74 A sample of chloroform being used as anesthetic is tested by Fehling solution Ammonical Cu 2 Cl 2 AgNO 3 solution AgNO 3 solution after boiling with alcoholic KOH solution The impurity HCl reacts with AgNO 3 to give ppt AgCl Q. No. 75 Chloroform for anesthetic purposes is tested for its purity with the reagent Silver nitrate Lead nitrate Ammonia Cal Cu 2 Cl 2

31 Lead nitrate The impurity HCl reacts with AgNO 3 to give ppt AgCl Q. No. 77 Haloforms are trihalogen derivatives of Ethane Methane Propone Benzene Q. No. 78 Number of bonds 6 Zero 3 12 present in B.H.C. (Benzene hex chloride) are bonds = zero. Q. No. 79 CCl 4 cannot give precipitate with AgNO 3 due to Formation of complex with AgNO 3 Evolution of Cl 2 gas Chloride ion is not formed AgNO 3 does not give silver ion Correct Answer 3 Q. No. 81 In the following sequence of reaction KOH alc KOH aq. CH CH CH Br A B C, The product (C) is Propane 2 ol HBr

32 Propane 1 ol Propyne Propene Q. No. 82

33 Q. No. 83 Consider the following sequence of reaction The product B is

34 Correct Answer 3 Q. No. 84 What is the major product of the reaction sequence? Q. No. 85 Consider the following reactions, The end product S is :

Indian School Muscat. Chemistry IIT - JEE

Indian School Muscat. Chemistry IIT - JEE Indian School Muscat Chemistry IIT - JEE HALOALKANES AND HALOARENES 1. Which one of the following is not formed when a mixture of methyl bromide and bromobenzene is heated with sodium metal in the presence