Chapter 25

Match the following: List I (Reagent) 1\. \(\mathrm{Cl}_{2}+\mathrm{AlCl}_{3}\) 2\. \(\mathrm{HNO}_{3}+\mathrm{H}_{2} \mathrm{SO}_{4}\) 3\. \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{7}\) 4\. \(\mathrm{Br}_{2}+\mathrm{Fe}\) List II (Electrophiles) (i) \(\mathrm{NO}_{2}\) (ii) \(\mathrm{Cl}_{\ldots} . \mathrm{Cl} \ldots \mathrm{AlCl}_{3}\) or \(\mathrm{Cl}^{+}\) (iii) \(\mathrm{SO}_{3} \mathrm{H}\left(\right.\) or \(\left.\mathrm{H}_{2} \mathrm{SO}_{4}+\mathrm{SO}_{3}\right)\) (iv) \(\mathrm{SO}_{3}\) (v) Br...Br...FeBr \(_{3}\) or \(\mathrm{Br}^{+}\)

Place the following compounds in the decreasing order of their relative reactivity with electrophile \(\left(\mathrm{E}^{+}\right)\). 1\. p-nitrochlorobenzene 2\. 2,4 -dinitrochlorobenzene 3\. chlorobenzene (a) \(3>1>2\) (b) \(1 \geq 2>3\) (c) \(2>1>3\) (d) \(3>2>1\)

Consider the given statements about the molecule \(\left(\mathrm{H}_{3} \mathrm{C}\right)_{2} \mathrm{CH}-\mathrm{CH}=\mathrm{CH}-\mathrm{C}=\mathrm{C}-\mathrm{CH}=\mathrm{CH}_{2}\) 1\. three carbons are sp \(^{3}\) hybridized 2\. three carbons are sp \(^{2}\) hybridized 3\. two carbons are sp hybridized Of these statements (a) 1 and 2 are correct (b) 1 and 3 are correct (c) 2 and 3 are correct (d) all are correct

Which one of the following would, on ozonolysis, yields \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\) and \(\mathrm{CH}_{2}(\mathrm{CHO})_{2}\) in the ratio \(1: 1\) ? (a) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CH}-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}=\mathrm{C}\left(\mathrm{CH}_{3}\right)_{2}\) (b) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{C}\left(\mathrm{CH}_{3}\right)_{2}\) (c) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{C}\left(\mathrm{CH}_{3}\right)_{2}\) (d) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{C}\left(\mathrm{CH}_{3}\right)=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{CH}-\) \(\mathrm{CH}_{3}\)

The correct reactions are (a) \(\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HBr} \rightarrow\) \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Br}\) (b) \(\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HCl} \rightarrow\) \(\mathrm{CH}_{3}-\mathrm{CH}(\mathrm{Cl})-\mathrm{CH}_{3}\) (c) \(\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HI} \stackrel{\text { peracide }}{\mathrm{HI}}\) \(\mathrm{CH}_{3}-\mathrm{CHI}^{2}-\mathrm{CH}_{3}\) (d) \(\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HBr} \stackrel{\text { peratide }}{\longrightarrow}\) \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Br}\)

Which of the following statement is/are correct? (a) \(\mathrm{H}_{2} \mathrm{C}=\mathrm{CH}_{2}+\mathrm{H}_{2} \stackrel{\mathrm{Ni}}{\longrightarrow}\) product; the rate of reac- tion is \(\mathrm{k}_{1^{-}}\) \(\mathrm{HC}=\mathrm{CH}+\mathrm{H}_{2} \stackrel{\mathrm{Ni}}{\longrightarrow}\) product; the rate of reaction is \(\mathrm{k}_{2}\). Then \(\mathrm{k}_{2}>\mathrm{k}_{1}\) (b) Dehydration of alcohol is equally facilitated in acid as in basic medium. (c) The trans stereoisomer is formed when cyclohexene is brominated in presence of \(\mathrm{CCl}_{4}\).

Which of the following reagent (s) is/are used in the following chemical reaction? \(\mathrm{CH}_{3}-\mathrm{C}=\mathrm{C}-\mathrm{CH}_{2} \longrightarrow \mathrm{CH}_{2}-\mathrm{CO}-\mathrm{CO}-\mathrm{CH}_{2} \mathrm{CH}_{3}\) (a) Reductive ozonolysis (b) \(1 \% \mathrm{HgSO}_{4}\) dil. \(\mathrm{H}_{2} \mathrm{SO}_{4}\) (c) Cold aq. Dilute alkaline \(\mathrm{KMnO}_{4}\) (d) Reaction with \(\mathrm{Br}_{2}-\mathrm{H}_{2} \mathrm{O}\)

\(\mathrm{CH}=\mathrm{CH}+\mathrm{C}, \mathrm{H}_{6} \mathrm{OH} \stackrel{\mathrm{HgSO}_{4}}{\longrightarrow} \mathrm{Y} \stackrel{\mathrm{H}_{2} \mathrm{O}}{\longrightarrow} \mathrm{X} .\) \(\mathrm{X}\) is (a) \(\mathrm{CH}_{3} \mathrm{OH}\) (b) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\) (c) \(\mathrm{CH}_{3} \mathrm{CHO}+\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\) (d) \(\mathrm{CH}_{2}=\mathrm{CHOH}\)

Which of the following statements is not true ? (a) Acetylene is used in the preparation of butadiene. (b) Butyne \(-1\) gives red precipitate with ammoniacal cuprous chloride but Butyne \(-2\) will not (c) The number of sigma and pi- bonds in 1 - butene \(-3\) - yne are 8 and 4 respectively (d) Propene when heated with chlorine at \(500^{\circ} \mathrm{C}\) forms \(\mathrm{CH}_{2} \mathrm{ClCH}=\mathrm{CH}_{2}\)

Which of the following reactions will yield 2 , 2- dibromopropane? (a) \(\mathrm{CH}=\mathrm{CH}+2 \mathrm{HBr} \longrightarrow\) (b) \(\mathrm{H}_{2} \mathrm{CC}=\mathrm{CH}+2 \mathrm{HBr} \longrightarrow\) (c) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HBr} \longrightarrow\) (d) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CHBr}+\mathrm{HBr} \longrightarrow\)

\(2-\) chlorobutane is treated with alcoholic KOH. Number of alkenes formed is

\(\mathrm{CH}_{3}-\mathrm{CH}_{2} \mathrm{Na}+\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Br} \longrightarrow\) Number of hydrogen atoms attached to sp \(^{2}\) carbon in the product is

o - Xylene is methylated to get trimethyl benzene. The number of possible isomers is

\(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_{3} \stackrel{\mathrm{HBr}}{\longrightarrow}\) product \((\mathrm{s})\). Number of products possible in the above reaction is

Of the following reagents the number of them which will react with \(\mathrm{CH}_{3} \mathrm{MgBr}\) to give \(\mathrm{CH}_{4}\) is \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}, \mathrm{CH}_{3} \mathrm{SH}, \mathrm{CH}_{3} \mathrm{NH}_{2}, \mathrm{RC}=\mathrm{CR}, \mathrm{HCHO}\) \(\mathrm{RC}=\mathrm{CH}\)

Total number of monochlorination products that can be obtained on treating 1 - butene with \(\mathrm{Cl}_{2}\) in presence of light is

In an experimental determination of active hydrogens in an organic compound \((\mathrm{Z}), 0.450 \mathrm{~g}\) of compound \((\mathrm{Z})\) was treated with excess of \(\mathrm{CH}_{3} \mathrm{MgBr}\) when \(224 \mathrm{ml}\) of \(\mathrm{CH}_{4}\) was evolved at NTP. Compound (Z) has molar mass equal to \(90 \mathrm{~g}\) per mole. How many active hydrogens are present per molecule of the compound \((Z)\) ?

The number of possible enantiomeric pairs that can be produced during monochlorination of \(2-\) methyl butane is

On vigorous oxidation by permanganate solution, \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CHCH}_{2} \mathrm{CHO}\) gives (a) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CO}\) and \(\mathrm{OHCCH}_{2} \mathrm{CHO}\) (b) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}-\mathrm{CHCH}_{2} \mathrm{CHO}\) (c) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CO}\) and \(\mathrm{OHCCH}_{2} \mathrm{COOH}\) (d) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CO}\) and \(\mathrm{CH}_{3} \mathrm{COO}^{\circ} \mathrm{H}\)

Acetylene reacts with hypochlorous acid to form (a) \(\mathrm{Cl}_{2} \mathrm{CHCHO}\) (b) \(\mathrm{ClCH}_{2} \mathrm{COOH}\) (c) \(\mathrm{CH}_{3} \mathrm{COCl}\) (d) \(\mathrm{ClCH}_{2} \mathrm{CHO}\)

Acetylene does not react with \([2002]\) (a) \(\mathrm{Na}\) (b) ammonical \(\mathrm{AgNO}_{3}\) (c) \(\mathrm{HCl}\) (d) \(\mathrm{NaOH}\)

On mixing a certain alkane with chlorine and irradiating it with ultraviolet light, it forms only one monochloroalkane. This alkane could be (a) propane (b) pentane (c) isopentane (d) neopentane

Which one of the following has the minimum boiling point? (a) \(\mathrm{n}\)-butane (b) 1 -butyne (c) 1-butene (d) iso-butene

Acid catalysed hydration of alkenes except ethene leads to the formation of \(\quad\) [2005] (a) primary alcohol (b) secondary or tertiary alcohol (c) mixture of primary and secondary alcohols (d) mixture of secondary and tertiary alcohols

Elimination of bromine from 2-bromobutane results in the formation of (a) equimolar mixture of 1 and 2 -butene (b) predominantly 2-butene (c) predominantly 1-butene (d) predominantly 2-butyne

Reaction of one molecule of HBr with one molecule of 1,3 -butadiene at \(40^{\circ} \mathrm{C}\) gives predominantly (a) 3-bromobutene under kinetically controlled conditions (b) 1-bromo-2-butene under thermodynamically controlled conditions (c) 3-bromobutene under thermodynamically controlled conditions (d) 1-bromo-2-butene under kinetically controlled conditions.

HBr reacts with \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{OCH}_{3}\) under anhydrous conditions at room temperature to give (a) \(\mathrm{CH}_{3} \mathrm{CHO}\) and \(\mathrm{CH}_{3} \mathrm{Br}\) (b) \(\mathrm{BrCH}_{2} \mathrm{CHO}\) and \(\mathrm{CH}_{3} \mathrm{OH}\) (c) \(\mathrm{BrCH}_{2}-\mathrm{CH}_{2}-\mathrm{OCH}_{3}\) (d) \(\mathrm{H}_{3} \mathrm{C}-\mathrm{CHBr}-\mathrm{OCH}_{3}\)

The reaction of toluene with \(\mathrm{Cl}_{2}\) in presence of \(\mathrm{FeCl}_{3}\) gives predominantly: (a) benzyl chloride (b) 0 - and p-chlorotoluene (c) m-chlorotoluene (d) benzoyl chloride

The compound formed as a result of oxidation of ethyl benzene by \(\mathrm{KMnO}_{4}\) is: (a) acetophenone (b) benzoic acid (c) benzyl alcohol (d) benzophenone

Which of the following reactions will yield 2,2 dibromopropane? \(\quad\) (a) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CHBr}+\mathrm{HBr} \longrightarrow\) (b) \(\mathrm{CH}=\mathrm{CH}+2 \mathrm{HBr} \longrightarrow\) (c) \(\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}+\mathrm{HBr} \longrightarrow\) (d) \(\mathrm{CH}_{3}-\mathrm{C}=\mathrm{CH}+2 \mathrm{HBr}\)

Toluene in nitrated and the resulting product is reduced with tin and hydrochloric acid. The product so obtained is diazotized and then heated with cuprous bromide. The reaction mixture so formed contains (a) Mixture of o- and p-bromotoluenes (b) Mixture of o- and p-dibromobenzenes (c) Mixture of o- and p-bromoanilines (d) Mixture of o- and m-bromotoluenes

In the following sequence of reactions, the alkene affords the compound ' \(\mathrm{B}\) ' \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CHCH}_{3} \stackrel{\mathrm{O}_{3}}{\longrightarrow}\) (A) \(\stackrel{\mathrm{H}_{2} \mathrm{O}}{\mathrm{Zn}}\) (B) The compound (B) is (a) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CHO}\) (b) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\) (c) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COCH}_{3}\) (d) \(\mathrm{CH}_{3} \mathrm{CHO}\)

The hydrocarbon which can react with sodium in liquid ammonia is (a) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{C}=\mathrm{CCH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{C}=\mathrm{CH}\) (c) \(\mathrm{CH}_{3} \mathrm{CH}^{2}=\mathrm{CHCH}_{3}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{C}=\mathrm{CCH}_{2} \mathrm{CH}_{3}\)

The alkene that exhibits geometrical isomerism is: (a) 2 -methyl propene (b) 2 -butene (c) 2 -methyl-2-butene (d) propene

One mole of a symmetrical alkene on ozonolysis gives two moles of an aldehyde having a molcular mass of \(44 \mathrm{u}\). The alkene is (a) Propene (b) I-butene (c) 2-butene (d) ethane

The main product of the following reaction is \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{CH}(\mathrm{OH}) \mathrm{CH}\left(\mathrm{CH}_{3}\right)_{2} \stackrel{\text { conc. } \mathrm{H}_{2} \mathrm{SO}_{4}}{\longrightarrow}\) ?

Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the presence of (a) a vinyl group (b) an isopropyl group (c) an acetylenic triple bond (d) two ethylenic double bonds

2-Hexyne gives trans \(-2\) - Hexene on treatment with (a) \(\mathrm{Pd} / \mathrm{BaSO}_{4}\) (b) \(\mathrm{Li} / \mathrm{NH}_{3}\) (c) \(\mathrm{Pt} / \mathrm{H}_{2}\) (d) \(\mathrm{LiAlH}_{4}\)

Which branched chain isomer of the hydrocarbon with molecular mass 72 u gives only one isomer of mono substituted alkyl halide? (a) Isohexane (b) Neopentane (c) Tertiary butyl chloride (d) Neohexane

A gaseous hydrocarbon given upon combustion \(0.72 \mathrm{~g}\) of water and \(3.08 \mathrm{~g}\) of \(\mathrm{CO}_{2}\). The empirical formula of the hydrocarbon is \([2013]\) (a) \(\mathrm{C}_{6} \mathrm{H}_{5}\) (b) \(\mathrm{C}_{?} \mathrm{H}_{8}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{4}\) (d) \(\mathrm{C}_{3} \mathrm{H}_{4}\)

The major organic compound formed by the reaction of \(1,1,1\)-trichloroethane with silver powder is: (a) 2-Butyne (b) 2 -Butene (c) Acetylene (d) Ethene