Chapter 26

C-X bond is strongest in (a) \(\mathrm{CH}_{3} \mathrm{Br}\) (b) \(\mathrm{CH}_{3} \mathrm{Cl}\) (c) \(\mathrm{CH}_{3} \mathrm{I}\) (d) \(\mathrm{CH}_{3} \mathrm{~F}\)

C-Cl bond of chlorobenzene in comparison to \(\mathrm{C}-\mathrm{Cl}\) bond in methyl chloride is (a) shorter and weaker (b) shorter and stronger (c) longer and weaker (d) longer and stronger

\(\mathrm{C}_{3} \mathrm{H}_{8}+\mathrm{Cl}_{2} \stackrel{\text { Light }}{\longrightarrow} \mathrm{C}_{3} \mathrm{H}_{7} \mathrm{Cl}+\mathrm{HCl}\) is an example of (a) elimination (b) substitution (c) addition (d) rearrangement reaction

The starting substance for the preparation of iodoform is any one of the following, except (a) \(\mathrm{CH}_{3} \mathrm{CH}(\mathrm{OH}) \mathrm{CH}_{3}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\) (c) \(\mathrm{HCH}_{2} \mathrm{OH}\) (d) \(\mathrm{CH}_{3} \mathrm{COOH}_{3}\)

The following structural formula refers to Clc1ccc(C(c2ccc(Cl)cc2)C(Cl)(Cl)Cl)cc1 (a) DDT (b) RNA (c) DNA (d) \(\mathrm{BHC}\)

\(\mathrm{Cl}_{2}\) reacts with \(\mathrm{CS}_{2}\) in presence of \(\mathrm{I}_{2}\) to form (a) \(\mathrm{CCl}_{4}\) (b) \(\mathrm{Cl}_{3} \mathrm{C}-\mathrm{NO}_{2}\) (c) \(\mathrm{CHCl}_{3}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl}\)

The alkyl halide is converted into an alcohol by (a) substitution (b) addition (c) elimination (d) dehydrohalogenation

Which of the following alkyl halides is used as a methylating agent? (a) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{Cl}\) (b) \(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{Cl}\) (c) \(\mathrm{CH}_{3} \mathrm{I}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{Br}\)

Of the following compounds, the one with the lowest boiling point is? (a) pentyl chloride (b) tertiary butyl chloride (c) isobutyl chloride (d) \(\mathrm{n}\)-butyl chloride

Which among MeX, \(\mathrm{RCH}_{2} \mathrm{X}, \mathrm{R}_{2} \mathrm{CHX}, \mathrm{R}_{3} \mathrm{CX}\) is most reactive towards \(S_{N}{\underline{\phantom{xx}}}^{2}\) reaction? (a) \(\mathrm{R}_{3} \mathrm{CX}\) (b) \(\mathrm{RCH}_{2} \mathrm{X}\) (c) \(\mathrm{R}_{2} \mathrm{CHX}\) (d) MeX

Correct order of boiling point for the alkyl halide is (a) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Br}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{I}\) (b) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{I}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Br}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{I}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Br}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Br}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{I}>\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl}\)

Substitution of chlorine takes place at higher temperature in (a) \(\mathrm{CH}_{2}=\mathrm{CH}_{2}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CH}_{2}\) (c) \(\mathrm{CH} \equiv \mathrm{CH}\) (d) none of the above

Chlorobenzene on heating with \(\mathrm{NH}_{3}\) under pressure in the presence of cuprous chloride gives (a) nitrobenzen (b) aniline (c) benzamide (d) 0 - and p-chloroaminobenzene

The most reactive halide towards \(\mathrm{SN}_{1}\) reaction is (a) sec-butyl chloride (b) tert-butyl chloride (c) n-butyl chloride (d) allul chloride

The number of dibromo derivatives of propane are (a) 5 (b) 4 (c) 3 (d) 2

1,1-dibromoethane when heated with zinc dust produces (a) ethyl bromide (b) ethene (c) vinyl bromide (d) 2 -butene

The order of reactivity of alkyl halides towards elimination reaction is (a) \(1^{\circ}>2^{\circ}>3^{\circ}\) (b) \(2^{\circ}>1^{\circ}>3^{\circ}\) (c) \(3^{\circ}>2^{\circ}>1^{\circ}\) (d) \(3^{\circ}>1^{\circ}>2^{\circ}\)

Which of the following are arranged in the decreasing order of dipole moment? (a) \(\mathrm{CH}_{3} \mathrm{Cl}, \mathrm{CH}_{3} \mathrm{Br}, \mathrm{CH}_{3} \mathrm{~F}\) (b) \(\mathrm{CH}_{3} \mathrm{Cl}, \mathrm{CH}_{3} \mathrm{~F}, \mathrm{CH}_{3} \mathrm{Br}\) (c) \(\mathrm{CH}_{3} \mathrm{Br}, \mathrm{CH}_{3} \mathrm{Cl}, \mathrm{CH}_{3} \mathrm{~F}\) (d) \(\mathrm{CH}_{3} \mathrm{Br}, \mathrm{CH}_{3} \mathrm{~F}, \mathrm{CH}_{3} \mathrm{Cl}\)

The reactivity order of halides for dehydrohalogenation is (a) \(\mathrm{R}-\mathrm{F}>\mathrm{R}-\mathrm{Cl}>\mathrm{R}-\mathrm{Br}>\mathrm{R}-\mathrm{I}\) (b) \(\mathrm{R}-\mathrm{I}>\mathrm{R}-\mathrm{Br}>\mathrm{R}-\mathrm{Cl}>\mathrm{R}-\mathrm{F}\) (c) \(\mathrm{R}-\mathrm{I}>\mathrm{R}-\mathrm{Cl}>\mathrm{R}-\mathrm{Br}>\mathrm{R}-\mathrm{F}\) (d) \(\mathrm{R}-\mathrm{F}>\mathrm{R}-\mathrm{I}>\mathrm{R}-\mathrm{Br}>\mathrm{R}-\mathrm{Cl}\)

Which of the alkyl halides on conversion into the Grignard reagent followed by treatment with water, will yield n-pentane? (a) 1-bromopentane (b) 2-bromopentane (c) 3-bromopentane (d) all of the above

Mg reacts with alkyl bromide best in (a) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{OCH}_{3}\) (b) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{~N}\left(\mathrm{CH}_{3}\right)_{2}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OC}_{2} \mathrm{H}_{5}\) (d) equally in all the three

Westron, a good industrial solvent, is (a) acetylene tetrachloride (b) trichloroethylene (c) dichlorodifluoromethane (d) hexachlorocyclohexane

On warming with silver powder, chloroform is converted into (a) hexachloroethane (b) acetylene (c) ethylene (d) carbon

A yellow product is formed when an organic compound \(\mathrm{C}_{3} \mathrm{H}_{8} \mathrm{O}\) is warmed with aqueous sodium carbonate and iodine solution. The product formed is (a) iodoform (b) sodium iodate (c) sodium iodide (d) adduct of \(\mathrm{NaI}\) and \(\mathrm{C}_{3} \mathrm{H}_{3} \mathrm{O}\)

Which of the following reacts with chloroform and base to form phenyl isocyanide? (a) nitrobenzene (b) phenol (c) chlorobenzene (d) aniline

Which of the following will react with water? (a) \(\mathrm{CHCl}_{3}\) (b) \(\mathrm{Cl}_{3} \mathrm{CCHO}\) (c) \(\mathrm{CCl}_{4}\) (d) \(\mathrm{ClCH}_{2} \mathrm{CH}_{2} \mathrm{Cl}\)

The major product in the reaction $$ \mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{Br} \stackrel{\mathrm{AgCN}}{\longrightarrow} ? \text { is } $$ (a) \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CN}\) (b) \(\mathrm{CH}_{3}-\mathrm{CH}_{2} \mathrm{Ag}\) (c) \(\mathrm{CH}_{3}-\mathrm{CH}_{2} \mathrm{NC}\) (d) none of these

In the reaction of \(\mathrm{p}\)-chlorotoluene with \(\mathrm{KNH}_{2}\) in liquid \(\mathrm{NH}_{3}\), the major product is (a) o-toluidine (b) \(\mathrm{m}\)-toluidine (c) p-toluidine (d) p-chloroaniline

Chlorination of toluene in presence of light and heat followed by treatment with aqueous NaOH gives (a) o-cresol (b) p-cresol (c) 2,4 -dihydroxytoluene (d) benzoic acid

Iodoform test is not given by (a) 2 -pentanone (b) ethanol (c) ethanal (d) 3 -pentanone

Freon-12 is commonly used as (a) refrigerant (b) a solvent (c) insecticide (d) a fire extinguisher

Propene when heated with \(\mathrm{Cl}_{2}\) at \(500^{\circ} \mathrm{C}\) forms (a) \(\mathrm{CH}_{3}-\mathrm{CHCl}-\mathrm{CH}_{2} \mathrm{Cl}\) (b) \(\mathrm{CH}_{2} \mathrm{Cl}-\mathrm{CH}=\mathrm{CH}_{2}\) (c) \(\mathrm{CH}_{2} \mathrm{Cl}-\mathrm{CHCl}-\mathrm{CH}_{2} \mathrm{Cl}\) (d) all of these

Which of the following pairs is correctly matched? (a) \(\mathrm{R}-\mathrm{Cl} \frac{\mathrm{Nal}}{\text { Acetone }}\) Finkelstain reaction (b) \(\mathrm{R}-\mathrm{X} \stackrel{\mathrm{Na}}{\longrightarrow}\) Frankland reaction (c) \(\mathrm{R}-\mathrm{X} \stackrel{\mathrm{Zn} / \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}}{\longrightarrow}\) Wurtz reaction \(\mathrm{X}\) (d) \(\mathrm{CH}_{3}-\mathrm{CH}-\mathrm{CH}_{3} \stackrel{\text { Alc. KOH }}{\rightarrow}\) Grignard reaction

Ethyl bromide reacts with lead-sodium alloy to form (a) tetramethyl bromide (b) tetraethyl lead (c) both (a) and (b) (d) none of these

Which of the following compounds gives a positive iodoform test? (a) 2-phenylethanol (b) pentanal (c) 3 -pentanol (d) 1 -phenylethanol

Butanitrile is formed by reaction of \(\mathrm{KCN}\) with (a) butyl chloride (b) propyl chloride (c) butyl alcohol (d) propyl alcohol

Which of the following will not give iodoform test? (a) ethanal (b) benzyl alcohol (c) ethanol (d) isopropyl alcohol

Carbon tetrachloride does have not dipole moment because of (a) its planar structure (b) its regular tetrahedral structure (c) similar sizes of carbon and chlorine atoms (d) similar electron affinities of carbon and chlorine

Toluene when refluxed with \(\mathrm{Br}_{2}\) in the presence of light mainly gives (a) p-bromotoluene (b) benzyl bromide (c) o-bromotoluene (d) mixture of o- and p-bromotoluene

Chloroform when reacts with nitric acid, gives (a) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{C}(\mathrm{NO})_{5} \mathrm{SH}\) (b) \(\mathrm{CCl}_{3} \mathrm{CHOH}\) (c) \(\mathrm{CCl}_{3} \mathrm{NO}_{2}\) (d) \(\mathrm{CCl}_{3} \mathrm{NO}_{3}\)

On sulphonation of \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{Cl}\) (a) m-chlorobenzenesulphonic acid is formed (b) benzene sulphonic acid is formed (c) o-chlorobenzene sulphonic acid is formed (d) 0 - and \(\mathrm{p}\)-chlorobenzene sulphonic acid is formed

Toluene on reaction with n-bromosuccinimide gives (a) phenyl bromomethane (b) o-bromomethyl benzene (c) p-bromomethyl benzene (d) m-bromomethyl benzene

Unpleasant smell of carbylamine is produced when chloroform and alcoholic KOH are heated with (a) any amine (b) any aliphatic amine (c) any aromatic amine (d) any primary amine

Which one of the following is mainly responsible for depletion of ozone layer? (a) water (b) carbon dioxide (c) chlorofluorocarbons (d) methane

The reaction on an alkyl halide with RCOOAg produces (a) ester (b) aldehyde (c) ether (d) ketone

A compound that will produce an offensive smell when heated with chloroform and alcoholic potash is (a) \(\left(\mathrm{C}_{2} \mathrm{H}_{3}\right)_{2} \mathrm{NH}\) (b) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{~N}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{NH}_{2}\) (d) \(\mathrm{CH}_{3} \mathrm{CN}\)

CCC(C)Cl (a) meso-form (b) racemic mixture (c) d-form (d) l-form

2-bromopentane reacts with alcoholic KOH to give (a) cis-2-pentene (b) trans-2-pentene (c) 1 -pentene (d) none of the above

Isopropyl chloride undergoes hydrolysis by (a) \(\mathrm{S}_{\mathrm{N}} 1\) and \(\mathrm{S}_{\mathrm{N}}^{2}\) mechanisms (b) neither \(\mathrIsopropyl chloride undergoes hydrolysis by (a) \)\mathrm{S}_{\mathrm{N}} 1\( and \)\mathrm{S}_{\mathrm{N}}^{2}\( mechanisms (b) neither \)\mathrm{S}_{\mathrm{N}}_{1}\( nor \)\mathrm{SN}_{2}\( mechanisms (c) \)\mathrm{S}_{\mathrm{N}}_{1}\( mechanism only (d) \)\mathrm{S}_{\mathrm{N}^{2}}\( mechanism onlym{S}_{\mathrm{N}}_{1}\) nor \(\mathrm{SN}_{2}\) mechanisms (c) \(\mathrm{S}_{\mathrm{N}}_{1}\) mechanism only (d) \(\mathrm{S}_{\mathrm{N}^{2}}\) mechanism only

Which one of the following is most reactive towards nucleophillic substitution reaction? (a) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{Cl}\) (b) \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{Cl}\) (c) \(\mathrm{ClCH}_{2}-\mathrm{CH}=\mathrm{CH}_{2}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CH}-\mathrm{Cl}\)