hitechpathshala

Q. 1

(A) III < II < I < IV

(B) IV < I < II < III

(C) I < II < III < IV

(D) I < IV < III < II

Q. 2

Q.2 The compound with molecular formula C4H6 has -

(A) One double bond

(B) One triple bond or two double bonds

(C) All single bonds

(D) One triple bond and one double bond

Q. 3

Q.3 Which of the following statemetns is not correct about ethyne -

(A) It belongs to the homologous series with general formula CnH2n – 2 where n = 2,3 etc

(B) It is a linear molecule with bond angles of 180o

(C) It has a triple bond in which the two carbon atoms share 6 electrons

(D) It undergoes electrophilic addition more readily than ethene

Q. 4

Q. 5

Q.5 The relative acidity of ethyne, ethene and ethane follows the order -

(A) Ethane > Ethyne < Ethene

(B) Ethyne > Ethene > Ethane

(C) Ethyne < Ethene < Ethane

(D) Ethene < Ethane < Ethyne

Q. 6

Q.6 In acetylene molecule, there are ... bonding electrons in between the carbon atoms –

(A) 6

(B) 8

(C) 2

(D) 4

Q. 7

Q.7 pKa of propane (I), propene (II) and propyne (III) will have the correct order –

(A) I > II > III

(B) III > II > I

(C) II > I > III

(D) None of these

Q. 8

Q. 9

Q.9 1-Butyne is formed when ethyl bromide is heated with -

(A) Sodium ethoxide

(B) Silver acrylate

(C) Sodium acetylide

(D) Silver acetate

Q. 10

Q.10 Which can yield acetylene in single step

(A) Propyne

(B) Ethene

(C) Ethylene dichloride

(D) Sodium acetate

Q. 11

Q.11 Which one of the following formula correctly represents the organic compound formed when 1,2-dibromoethane is heated with NaOH in ethanol solution ?

(A) C2H2

(B) C2H4

(C) C2H6

(D) CH3OH

Q. 12

(A) 4-Methyl-2-pentyne

(B) Propyne

(C) Propyne and propene

(D) A mixture of propene, propyne and 4-methyl- 2-pentyne

Q. 13

Q. 14

Q.14 Acetylene may be prepared using Kolbe's electrolytic method employing -

(A) Pot. acetate

(B) Pot. succinate

(C) Pot. fumarate

(D) None of these

Q. 15

Q. 16

Q.16 Acetylene is prepared industrially by passingcelectric discharge through graphite electrods in the atmosphere of -

(A) Air

(B) N2

(C) H2

(D) CO2

Q. 17

Q. 18

Q. 19

Q.19 Which of the following method is not appli- cable to the preparation of acetylene -

(A) Dehydro chlorination of a vicinal dihalide with two carbon atoms

(B) Debromination of tetrabromoethane

(C) Dehydration of glycol

(D) Heating of vinyl chloride with sodamide

Q. 20

Q.20 Propyne is formed by heating 1,2-dibromopropane with –

(A) C2H5ONa

(B) Alc. KOH and sodamide

(C) Aqueous alkali

(D) Sodalime

Q. 21

Q.21 Acetylene hydrocarbons are acidic because

(A) Sigma electron density of C–H bond in acetylene is nearer a carbon which has 50% s-character

(B) Acetylene has only one hydrogen atom at each carbon atom

(C) Acetylene contains least number of hy- drogen atoms among the possible hydro- carbons having two carbons

(D) Acetylene belongs to the class of alkynes with formula CnH2n – 2

Q. 22

Q. 23

Q.23 The reaction shown by 1-alkyne is –

(A) Addition

(B) Substitution

(C) Polymerisation

(D) All of the above

Q. 24

Q.24 Lindlar’s catalyst consists of –

(A) Metallic nickel + nickel boride

(B) Metallic platinum

(C) Metallic palladium deposited on calcium carbonate containing lead acetate and quinoline

(D) Sodium borohydride in ethanol.

Q. 25

Q.25 Ethyne adds on HCl to first give a –

(A) Carbanion

(B) A free radical

(C) A vinylic cation

(D) A biradical

Q. 26

Q. 27

Q.27 The reduction of an alkyne to alkene using Lindlar's catalyst results into -

(A) Cis addition of hydrogen atoms

(B) Trans addition of hydrogen atoms

(C) A mixture obtained by cis and trans additions of hydrogen which are in equilibrium with each other

(D) A mixture obtained by cis and trans additions of hydrogen atoms which are not in equilibrium with each other

Q. 28

Q.28 The reduction of 3-hexyne with H2/Lindlar's catalyst gives predominantly -

(A) n-Hexane

(B) Trans-3-hexene

(C) Cis-3-hexene

(D) A mixture of cis-and trans-3-hexene

Q. 29

Q. 30

Q.30 By the action of hydrobromic acid on ethyne we get -

(A) Methyl iodide

(B) Ethyl iodide

(C) Ethyledene bromide

(D) 1, 2-Dibromo ethane

Q. 31

(A) COCH3

(B) CH2CHO

(C) COCH3

(D) CH2CHO

Q. 32

Q.32 The products obtained via oxymercuration (HgSO4+ H2SO4) of 1-butyne would be -

(A) CH2CH2COCH3

(B) CH3CH2CH2CHO

(C) CH3CH2CHO + HCHO

(D) CH3CH2COOH + HCOOH

Q. 33

(A) HgSO4

(B) Pd

(C) Pt

(D) AlCl3

Q. 34

Q.34 Reaction of alkenes and alkynes withv hypochlorous acid is called -

(A) Hydroxy chlorination

(B) Chlorohydroxylation

(C) Chlorination

(D) Hydroxylation

Q. 35

Q.35 Hydration of propyne gives -

(A) 1-Propanol

(B) 2-Propanol

(C) Propanal

(D) Propanone

Q. 36

Q.36 By the addition of CO and H2O on ethyne, the following is obtained -

(A) Propenoic acid

(B) Propanal

(C) 2-Propenoic acid

(D) None of these

Q. 37

Q. 38

Q.38 An alkyne which gives two moles of acetic acid on ozonolysis is -

(A) 1-Butyne

(B) 2-Butyne

(C) Methyl acetylene

(D)3-methyl-1-butyne

Q. 39

Q.39 Propyne on oxidation with SeO gives -

(A) Penta-1,4-diene

(B) Penta-1,3-diene

(C) Penta-1,2-diene

(D) None

Q. 40

(A) 3-Hexyne

(B) 2-Methyl-3-hexyne

(C) 2-Methyl-2-hexyne

(D) 2-Methyl-2-hexene

Q. 41

Q.41 Which one of these will react with sodium metal -

(A) Ethyne

(B) Ethene

(C) Ethane

(D) Ether

Q. 42

Q. 43

Q. 44

Q.44 Which of the following compounds will not give a precipitate with tollen's reagent -

(A) Ethyne

(B) 1-Butyne

(C) 3-Methyl-1-butyne

(D) 2-Pentyne

Q. 45

Q.45 A mixture of CH4 , C2H4 and C2H2 gases are passed through a Wolf bottle containing ammonical cuprous chloride. The gas com-ing out is -

(A) Methane

(B) Acetylene

(C) Mixture of methane and ethylene

(D) Original mixture

Q. 46

Q. 47

Q.47 When acetylene is passed into a solution of cuprous chloride and ammonium chloride, it forms finally -

(A) Vinyl acetylene

(B) Divinyl acetylene

(C) Chloroprene

(D) Poly vinyl acetylene

Q. 48

Q. 49

(A) Br2

(B) O3

(C) Cu2+

(D) KMnO4

Q. 50

CHEMISTRY QUIZ 28 (ALKYNE 1)

Marks: 200