995 + Interview Questions in HYDROCARBONS IN GENERAL AWARENESS Page 6 InterviewSolution

251.	Octane number can be changed byA. `C_(8)-C_(12)`B. `C_(2)-C_(5)`C. `C_(7)-C_(9)`D. None of these
Answer» Correct Answer - C

Discussion

252.	Octane number can be changed by:A. IsomerisationB. AlkylationC. CyclisationD. All of these
Answer» Correct Answer - D

Discussion

253.	Octane number is zero forA. n-HeptaneB. IsooctaneC. n-HetaneD. Isopheptane
Answer» Correct Answer - A Octane number is defined as the presence of isocotane by volume in a mixture of isooctane and n-heptane. Octane number of n-heptane is zero while octane number of isoocatane is 100

Discussion

254.	Heating a mixture of sodium benzoate and soda-lime givesA. BenzeneB. MethaneC. Sodium benzoateD. Calcium benzoate.
Answer» Correct Answer - A

Discussion

255.	How many of the following reactions,leads to the formation of diastereomers?
Answer» Correct Answer - 4 (b,d,e,f)

Discussion

256.	Arrange the halogens `F_(2),Cl_(2),Br_(2),I_(2)`, in order of their increasing reactivity with alkanes.A. `I_(2) lt Br_(2) lt Cl_(2) lt F_(2)`B. `Br_(2) lt Cl_(2) lt F_(2) lt I_(2)`C. `F_(2) lt Cl_(2) lt Br_(2) lt I_(2)`D. `Br_(2) lt I_(2) lt Cl_(2) lt F_(2)`
Answer» Correct Answer - A Rate of reaction of alkanes with halogens is `F_(2) gt Cl_(2) gt Br_(2) gt I_(2)`. Reactivity decreases down the group as the electronegativity of the halogen decreases down the group.

Discussion

257.	Arrange the halogens `F_2, Cl_2 , Br_2 , I_2` in order of their increasing reactivity with alkanes.A. `I_2 lt Br_2 lt Cl_2 lt F_2`B. `Br_2 lt Cl_2 lt F_2 lt I_2`C. `F_2 lt Cl_2 lt Br_2 lt I_2`D. `Br_2 lt I_2 lt Cl_2 lt F_2`
Answer» Correct Answer - A Reactivity decreases down the group as the electronegativity or the electrode potential of the halogen decreases down the group. Thus, option (a ) is correct

Discussion

258.	Ethyne adds on HCl to first give a-A. CarbanionB. A free radicalC. A vinylic cationD. A biradical
Answer» Correct Answer - C

Discussion

259.	Formation of polyethylene from calcium carbide takes place as follows `CaC_(2)+2 H_(2)O rarr Ca(OH)_(2)+C_(2)H_(2)` `C_(2)H_(2)+H_(2) rarr C_(2)H_(2)` `N(C_(2)H_(4)) rarr (-CH_(2)-CH_(2)-)_(n)` The amount of polyethylene obtained from `64.1 kg CaC_(2) ` isA. 7kgB. 14kgC. 21kgD. 28kg
Answer» Correct Answer - D 64kg of `CaC_(2)` produces ethylene=28kg Amount of polythene produced=28kg

Discussion

260.	To which of the following compounds `H_(2)` adds most readily?A. `CH_(2)=CH_(2)`B. `CH_(3)-CH=CH_(2)`C. `CH_(3)-CH=CH-CH_(3)`D. `CH_(3)-underset(CH_(3))underset(\|)(C)=CH-CH_(3)`
Answer» Correct Answer - A

Discussion

261.	Benzene adds on ozone to form a
Answer» Correct Answer - C `C_(6)H_(6)+O_(3) to underset("Benzene triozanide")(C_(6)H_(6)(O_(3))_(3))`

Discussion

262.	Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, E+ (a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene(b) Toluene, p-H3C – C6H4 – NO2, p-O2N – C6H4 – NO2.
Answer» Chlorobenzene> p-nitrochlorobenzene> 2,4-dinitrochlorobenzene Toluene> p-H₃C – C₆H₄ – NO₂>p-O₂N – C₆H₄ – NO₂

262.

Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, E+ (a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene(b) Toluene, p-H3C – C6H4 – NO2, p-O2N – C6H4 – NO2.

Answer»

Chlorobenzene> p-nitrochlorobenzene> 2,4-dinitrochlorobenzene

Toluene> p-H₃C – C₆H₄ – NO₂>p-O₂N – C₆H₄ – NO₂

Discussion

263.	An ethereal solution of an alkyl halide preferably the bromide of iodide, is treated with sodium `2R-X+2Na overset("Ether")toR-R+2NaX` `2CH_(3)-Br+2Na overset("Ether")toCH_(3)-CH_(3)+2NaBr` `CH_(3)CH_(2)Br+2Na+CH_(3)Br overset("Ether")toCH_(3)CH_(2)-CH_(3)+2NaBr` In this reaction, the product has new (C-C) bond with the same type of alkyl halide, the product has symmetery and this helps in deciding the nature of reacting halide. Intermediates are free radicals Formation of free radical takes place with absorbtion of minimum energy inA. `CH_(3)CH_(2)CH_(2)CH_(2)Br`B. `CH_(3)-underset(CH_(3))underset(\|)(CH)CH_(2)Br`C. `CH_(3)-underset(CH_(3))underset(\|)(CH)CH_(2)CH_(3)`D. `(CH_(3))_(3)C-Br`
Answer» Correct Answer - D

Discussion

264.	An ethereal solution of an alkyl halide preferably the bromide of iodide, is treated with sodium `2R-X+2Na overset("Ether")toR-R+2NaX` `2CH_(3)-Br+2Na overset("Ether")toCH_(3)-CH_(3)+2NaBr` `CH_(3)CH_(2)Br+2Na+CH_(3)Br overset("Ether")toCH_(3)CH_(2)-CH_(3)+2NaBr` In this reaction, the product has new (C-C) bond with the same type of alkyl halide, the product has symmetery and this helps in deciding the nature of reacting halide. Intermediates are free radicals `CH_(3)CH_(2)CH_(2)CH_(3) underset("hv controlled")overset(Cl_(2))to overset("Na//ether")to` Major product of the above reaction isA. `CH_(3)(CH_(2))_(6)CH_(3)`B. `CH_(3)-CH_(2)-underset(CH_(3))underset(\|)(CH)-underset(CH_(3))underset(\|)(CH)CH_(2)CH_(3)`C. `CH_(3)-underset(CH_(3))underset(\|)(CH)-CH_(2)CH_(2)underset(CH_(3))underset(\|)(CH)CH_(3)`D. None of these
Answer» Correct Answer - B Intermediate is `CH_(3)CH_(2)CH_(2)CH_(3)`

Discussion

265.	An ethereal solution of an alkyl halide preferably the bromide of iodide, is treated with sodium `2R-X+2Na overset("Ether")toR-R+2NaX` `2CH_(3)-Br+2Na overset("Ether")toCH_(3)-CH_(3)+2NaBr` `CH_(3)CH_(2)Br+2Na+CH_(3)Br overset("Ether")toCH_(3)CH_(2)-CH_(3)+2NaBr` In this reaction, the product has new (C-C) bond with the same type of alkyl halide, the product has symmetery and this helps in deciding the nature of reacting halide. Intermediates are free radicals 1-Bromo-3-chlroro cyclobutane combines with Na/ether to yieldA. B. C. D.
Answer» Correct Answer - C Bond energy of C-Br is lower than that fo C-Cl coupling of C-C bond takes place from bromine side

Discussion

266.	Alcoholic solution of caustic potash is a specific reagent forA. DehydrationB. DehydrohalogenationC. DehydrogenationD. Hydration.
Answer» Correct Answer - B

Discussion

267.	Alcoholic solution of caustic potash is a specific reagent forA. DehydrationB. DehydrohalogenationC. DehydrogenationD. Hydration
Answer» Correct Answer - b b

Discussion

268.	Lindane can be obtained by the reaction of benzene withA. `CH_(3)Cl//"anhyd". AlCl_(3)`B. `C_(2)H_(5)l//"anhyd."AlCl_(3)`C. `CH_(3)COCl//"anhyd."AlCl_(3)`D. `Cl_(2)` in sunlight
Answer» Correct Answer - D

Discussion

269.	Name the chemical name of lindane.
Answer» BHC (Benzene Hexachloride)

Discussion

270.	An unknown compound (A) has a molecular formula `C_(4)H_(6)`. When (A) is treated with excess of `Br_(2)` a new substance (B) with formula `C_(4)H_(6)Br_(4)`. Is formed (A) forms a white ppt. with ammonical silver nitrate solution. (A) may be,A. But-1-yneB. But-2-yneC. But-1-eneD. But-2-ene
Answer» Correct Answer - a `(A) H-C-=C-C-CH_(2)-CH_(3)`(Terminal alkeyne gives white ppt. with ammonical `AgNO_(3)`)

Discussion

271.	Addition of `X_(2)` on alkene is electrophilic additon reaction.Reaction proceed through the formation of 3- membered cyclic halonium ion. Nucleophile `X^(-)` attacks from backside of cyclic halonium ion hence total reaction is anti addition reaction.If this reaction proceed polar solvent then solvent itself acts as nucleophile. Which of the following statements is incorrect?A. Symmetrical trans alkene gives 2 products on reaction with `Br_(2)//CCI_(4)`B. Symmetrical cis alkene gives 2 products on reaction with `Br_(2)//C Cl_(4)`C. Trans alkenes give erythro productD. Cis alkenes give threo product
Answer» Correct Answer - A Trans-alkane give meso product which is optically inactive

Discussion

272.	Alkene and alkyne both undergo electrophilic additon beacuise of `pi` electron density, they behave as elctron rich species, alknens are more reactive toward this reaction because the intermiediate formed when an`E^(oplus)` adds to an alkyne is a vinylic cation wheras sthe intermediate formed when an `E^(oplus)` adds to akene is alkyl cation, which is mopre stable. A. B. C. D.
Answer» Correct Answer - A Electrophilic additon on a lakene is faster

Discussion

273.	Which of the following reactions give diastereomeric products?A. B. C. D.
Answer» Correct Answer - B::C Compound (b) and (c ) already contain chiral center so compound will forkm diasteromer.

Discussion

274.	The treatment of `CH_3MgX` with `CH_3C -= C-H` producesA. `CH_4`B. `CH_3-CH=CH_2`C. `CH_3C-=C-CH_3`D. `CH_3-oversetoversetH\|C=oversetoversetH\|C-CH_3`
Answer» Correct Answer - A `CH_3C-=C-H + CH_3MgX to CH_3C -= CMgX + CH_4`

Discussion

275.	Ethyne`+X overset(Ba^(2+))to`Prop-2-ene-nitrile. Here X can beA. BromineB. Barium cyanideC. Hydrogen bromideD. Hydrogen cyanide
Answer» Correct Answer - B `underset("Ethyne")(HC)-=CH+HCN overset(Ba^(2+))to underset("Prop-2-enertrile")(H_(2)C=CH-C-=N)`

Discussion

276.	Identify the reagent from the following list which can easily distinguish between 1-butyne and 2-butyneA. bromine , `C Cl_4`B. `H_2`, Lindlar catalystC. dilute `H_2SO_4, HgSO_4`D. ammoniacal `Cu_2Cl_2` solution
Answer» Correct Answer - D Amm. `Cu_2Cl_2` reacts with 1-butyne but not with 2-butyne

Discussion

277.	Which of the following reagents will be able to distinguish between 1-butyne and 2-butyne ?A. `NaNH_2`B. HClC. `O_2`D. `Br_2`
Answer» Correct Answer - A 1-Butyne being a terminal alkyne has an acidic hydrogen and hence reacts with `NaNH_2` to evolve `NH_3` gas but 2-butyne does not .

Discussion

278.	Ethyne is acidic in nature in comparison to ethene and ethane. Why is it so?
Answer» Hydrogen atoms in ethyne are attached to the sp hybirdised carbon atoms whereas they are attached to sp2 hybridized carbon atoms in ethene and sp3 hydridised carbons in ethane. Due to the maximum percentage of s – character (50%), the sp hybridized orbital’s of carbon atoms in ethyne molecules have highest etcetronegativity: Which attracts the shared pair of the C-H bond of ethyne to a greater extent than that of the sp² hybridized orbital’s of carbon in ethene and the sp3 hybridized orbital of carbon in ethane. Thus in ethyne molecule, hydrogen atoms can be liberated as protons more easily as compared to ethene and ethane.

Discussion

279.	How would you distinguish between butyne – 1 and butyne – 2?
Answer» Butyne – 1 (CH₃CH₂C ≡ CH), having an acetylene hydrogen atom will give white precipitate with ammonical silver nitrate and red precipitate with ammonical cuprous chloride. On the other hand, butyne – 2 (CH₃C ≡ C CH₃) having no acetylene hydrogen atom does not respond to either of the two reagent.

Discussion

280.	Why does benzene undergo electrophilic reactions easily and nucleophilic reactions with difficulty?
Answer» benzene has high electron density due to the presence of 3e^-pairs above and below the plane of the ring representing the double bond. Due to rich source of electrons benzene attracts the electrophile reagents towards it and repels nucleophile reagents.

Discussion

281.	Statement-I: Statement-II:Birch reduction is anti addition.A. If both statement-1 & statement-2 are true & the statement-II is a correct explanation of the statement-IB. If both statement-I & statement-II are true but statement-II si not a correct explanation of the statement-IC. If statement-I is true but the statement-II is false.D. If statement-I is false but the statement-II is true.
Answer» Correct Answer - D `Me-C-=overset(ɵ)(C)Na^(+)` is product.

Discussion

282.	Why does benzene undergo clectrophilic substitution reactions easily and nucleophilic substitution with difficulty?
Answer» Due to the presence of an electron cloud containing 6π – electrons above and below the plane of the ring, benzene is a rich source of electrons, Consequently, it attracts the electrophilic reagents towards it and repels the nucleophilic reagents. As a result, benzene undergoes electrophilic substitution reactions easily and nucleophilic substitution with difficulty.

Discussion

283.	Which of the following is less reactive than benzene towards electrophilic substitution reactions?(a) Nitrobenzene (b) Aniline (c) Bromobenzene (d) Chlorobenzene
Answer» (a) Nitrobenzene

Discussion

284.	Alkynes on reduction with sodium in liquid ammonia form trans alkenes. Will the butene thus formed on reduction of 2-butyne show the geometrical isomerism?
Answer» 2-Butene is capable of showing geometrical isomerism.

Discussion

285.	What is a Lindlar’s catalyst? What is it used for?
Answer» Pd deposited over CaCO₃ or BaSO₄ and partially poisoned by addition of lead acetate or sulphur or quinoline. It is used for partial reduction of alkynes to cis-alkenes.

Discussion

286.	Consider the following statements. (i) The process of reduction using sodium in liquid ammonia is called as Birch reduction. (ii) Birch reduction is stereospecific in reaction. (iii) Aleynes can be reduced to cis – alkenes using Birch reduction. Which of the above statement is/are correct’? (a) (i) and (ii)(b) (ii) and (iii) (c) (iii) only(d) (ii) only
Answer» Correct answer is (a) (i) and (ii)

Discussion

287.	Why benzene undergoes electrophilic substitution reaction where as alkenes undergoes addition reaction?
Answer» Benzene possess an unhybridised p-orbital containing one electron. The lateral overlap of theirp-orbitals produces 3 it bond. The six electron of the p-orbitais cover all the six carbon atoms and arc said to be delocalised. Due to delocalisation, strong it-bond is formed which makes the molecule stable. Therefore benzene undergoes electrophilic substitution reaction, whereas alkenes undergoes addition reaction.

Discussion

288.	Why benzene undergoes substitution reaction rather than addition reactions under normal conditions?
Answer» 1. Each carbon atom in henzene possess an unhybridised p-orbital containing one electron. The ateral overlap of their p-orbitais produces 3π- bond, six electrons of the p-orbitais over all the six carbon atoms and are said lo be delocalised. 2. Due to delocalisation, strong it-bond is formed which makes the molecule stable. Hence unlike alkenes and alkynes, benzene undergoes substitution reactions rather than addition reactions under normal conditions.

288.

Why benzene undergoes substitution reaction rather than addition reactions under normal conditions?

Answer»

1. Each carbon atom in henzene possess an unhybridised p-orbital containing one electron. The ateral overlap of their p-orbitais produces 3π- bond, six electrons of the p-orbitais over all the six carbon atoms and are said lo be delocalised.

2. Due to delocalisation, strong it-bond is formed which makes the molecule stable. Hence unlike alkenes and alkynes, benzene undergoes substitution reactions rather than addition reactions under normal conditions.

Discussion

289.	Alkynes undergoes reduction using sodium in liquid ammonia to give …………
Answer» Alkynes undergoes reduction using sodium in liquid ammonia to give trans – alkenes.

Discussion

290.	Alkynes undergoes reduction using Lindlar’s catalyst to give ………….
Answer» Alkynes undergoes reduction using Lindlar’s catalyst to give cix – alkenes.

Discussion

291.	The correct trend of acidic nature of the following alkynes isA. `CH-=CH gt CH_(3) - C-=CH gt CH_(3) C -=C CH_(3)`B. `CH_(3)-C -=CH gt CH -= CH gt CH_(3) C -= C CH_(3)`C. `CH_(3)C -= C CH_(3) gt CH_(3 - C-=CH gt CH -= CH`D. `CH-=CH gt CH_(3)C -= C CH_(3) gt CH_(3) C -=CH`
Answer» Correct Answer - A

Discussion

292.	Give reason: Acidic nature of alkynes is used to distinguish between terminal and nonterminal alkynes.
Answer» Acidic alkynes react with certain heavy metal ions like Ag⁺ and Cu⁺ and form insoluble acetylides. On addition of acidic alkyne to the solution of AgNO₃ in alcohol, it forms a precipitate, which indicates that the hydrogen atom is attached to triply bonded carbon. Hence, this reaction is used to differentiate terminal alkynes and non-terminal alkynes.

292.

Give reason: Acidic nature of alkynes is used to distinguish between terminal and nonterminal alkynes.

Answer»

Acidic alkynes react with certain heavy metal ions like Ag⁺ and Cu⁺ and form insoluble acetylides.
On addition of acidic alkyne to the solution of AgNO₃ in alcohol, it forms a precipitate, which indicates that the hydrogen atom is attached to triply bonded carbon.

Hence, this reaction is used to differentiate terminal alkynes and non-terminal alkynes.

Discussion

293.	Statements-I : Unlike alkenes and alkynes benzene undergoes substitution reactions rather than addition reaction under normal conditions. Statements-II : Because of the delocalisation of electrons a strong t bond is formed which makes the molecule stable. (a) Statement-I and II are correct and statement-II is correct explanation of statement-I. (b) Statement-I and II are correct but statement-II is not correct explanation of statement-I (c) Statement-I ¡s correct but statement-II is wrong. (d) Statement-I is wrong but statement-II is correct.
Answer» (a) Statement-I and II are correct and statement-II ls correct explanation of statemen-I.

Discussion

294.	Fine the odd one out: (a) Benzene(b) Ethane(c) Ethene (d) Propyne
Answer» Correct answer is (a) Benzene

Discussion

295.	Bond length of ethane (I), ethene (II), acetylene (III) and benzene (IV) follows the orderA. `I gt II gt III gt IV `B. `I gt II gt IV gt III`C. `I gt IV gt II gt III`D. `III gt IV gt II gt I`
Answer» Correct Answer - C

Discussion

296.	3-Hexyne reacts with Na/liq. `NH_(3)` to produceA. cis-3-HexeneB. trans-3-HexeneC. 3-HexylamineD. 2-Hexylamine
Answer» Correct Answer - B

Discussion

297.	Benzene and naphthalene form an ideal solution at room temperature. For this process,the true statement(s) is (are)A. `DeltaH` is positiveB. `DeltaS_("system")` is positiveC. `DeltaS("surroundings")=0`D. `DeltaH=0`
Answer» Correct Answer - B,C,D (B,C,D) when a non ionic solid (naphtalene) dissovles in a non polar solvent(benzene) `DeltaG` is -ve(as the process is spontanueous) `DeltaG`(system) is +ve (increase in entropy) S(surrounding)=0 and `DeltH`=0 (because benzene and napthalene form an ideal solution.)

Discussion

298.	Some meta-directing substituents in aromatic substitution are given which one is the most deactivating?A. `-NO_(2)`B. `-C-=N`C. `-SO_(3)H`D. `-COOH`
Answer» Correct Answer - A `-NO_(2)` group is not dactivating `(-R and -I`effect)

Discussion

299.	Some meta-directing substituents in aromatic substitution are given. Which one is most deactivating? (a) – COOH (b) – NO2(c) – C N (d) – SO3H
Answer» Correct answer is (b) – NO₂

Discussion

300.	Some meta-directing substituents in aromatic substitution are given.Which one is most deactivating ?A. `-COOH`B. `-NO_2`C. `-C-=N`D. `-SO_3H`
Answer» Correct Answer - B

Discussion

Explore topic-wise InterviewSolutions in .

Octane number can be changed byA. `C_(8)-C_(12)`B. `C_(2)-C_(5)`C. `C_(7)-C_(9)`D. None of these

Octane number can be changed by:A. IsomerisationB. AlkylationC. CyclisationD. All of these

Octane number is zero forA. n-HeptaneB. IsooctaneC. n-HetaneD. Isopheptane

Heating a mixture of sodium benzoate and soda-lime givesA. BenzeneB. MethaneC. Sodium benzoateD. Calcium benzoate.

How many of the following reactions,leads to the formation of diastereomers?

Arrange the halogens `F_(2),Cl_(2),Br_(2),I_(2)`, in order of their increasing reactivity with alkanes.A. `I_(2) lt Br_(2) lt Cl_(2) lt F_(2)`B. `Br_(2) lt Cl_(2) lt F_(2) lt I_(2)`C. `F_(2) lt Cl_(2) lt Br_(2) lt I_(2)`D. `Br_(2) lt I_(2) lt Cl_(2) lt F_(2)`

Arrange the halogens `F_2, Cl_2 , Br_2 , I_2` in order of their increasing reactivity with alkanes.A. `I_2 lt Br_2 lt Cl_2 lt F_2`B. `Br_2 lt Cl_2 lt F_2 lt I_2`C. `F_2 lt Cl_2 lt Br_2 lt I_2`D. `Br_2 lt I_2 lt Cl_2 lt F_2`

Ethyne adds on HCl to first give a-A. CarbanionB. A free radicalC. A vinylic cationD. A biradical

Formation of polyethylene from calcium carbide takes place as follows `CaC_(2)+2 H_(2)O rarr Ca(OH)_(2)+C_(2)H_(2)` `C_(2)H_(2)+H_(2) rarr C_(2)H_(2)` `N(C_(2)H_(4)) rarr (-CH_(2)-CH_(2)-)_(n)` The amount of polyethylene obtained from `64.1 kg CaC_(2) ` isA. 7kgB. 14kgC. 21kgD. 28kg

To which of the following compounds `H_(2)` adds most readily?A. `CH_(2)=CH_(2)`B. `CH_(3)-CH=CH_(2)`C. `CH_(3)-CH=CH-CH_(3)`D. `CH_(3)-underset(CH_(3))underset(|)(C)=CH-CH_(3)`

Benzene adds on ozone to form a

Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, E+ (a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene(b) Toluene, p-H3C – C6H4 – NO2, p-O2N – C6H4 – NO2.

Alcoholic solution of caustic potash is a specific reagent forA. DehydrationB. DehydrohalogenationC. DehydrogenationD. Hydration.

Alcoholic solution of caustic potash is a specific reagent forA. DehydrationB. DehydrohalogenationC. DehydrogenationD. Hydration

Lindane can be obtained by the reaction of benzene withA. `CH_(3)Cl//"anhyd". AlCl_(3)`B. `C_(2)H_(5)l//"anhyd."AlCl_(3)`C. `CH_(3)COCl//"anhyd."AlCl_(3)`D. `Cl_(2)` in sunlight

Name the chemical name of lindane.

An unknown compound (A) has a molecular formula `C_(4)H_(6)`. When (A) is treated with excess of `Br_(2)` a new substance (B) with formula `C_(4)H_(6)Br_(4)`. Is formed (A) forms a white ppt. with ammonical silver nitrate solution. (A) may be,A. But-1-yneB. But-2-yneC. But-1-eneD. But-2-ene

Which of the following reactions give diastereomeric products?A. B. C. D.

The treatment of `CH_3MgX` with `CH_3C -= C-H` producesA. `CH_4`B. `CH_3-CH=CH_2`C. `CH_3C-=C-CH_3`D. `CH_3-oversetoversetH|C=oversetoversetH|C-CH_3`

Ethyne`+X overset(Ba^(2+))to`Prop-2-ene-nitrile. Here X can beA. BromineB. Barium cyanideC. Hydrogen bromideD. Hydrogen cyanide

Identify the reagent from the following list which can easily distinguish between 1-butyne and 2-butyneA. bromine , `C Cl_4`B. `H_2`, Lindlar catalystC. dilute `H_2SO_4, HgSO_4`D. ammoniacal `Cu_2Cl_2` solution

Which of the following reagents will be able to distinguish between 1-butyne and 2-butyne ?A. `NaNH_2`B. HClC. `O_2`D. `Br_2`

Ethyne is acidic in nature in comparison to ethene and ethane. Why is it so?

How would you distinguish between butyne – 1 and butyne – 2?

Why does benzene undergo electrophilic reactions easily and nucleophilic reactions with difficulty?

Why does benzene undergo clectrophilic substitution reactions easily and nucleophilic substitution with difficulty?

Which of the following is less reactive than benzene towards electrophilic substitution reactions?(a) Nitrobenzene (b) Aniline (c) Bromobenzene (d) Chlorobenzene

Alkynes on reduction with sodium in liquid ammonia form trans alkenes. Will the butene thus formed on reduction of 2-butyne show the geometrical isomerism?

What is a Lindlar’s catalyst? What is it used for?

Why benzene undergoes electrophilic substitution reaction where as alkenes undergoes addition reaction?

Why benzene undergoes substitution reaction rather than addition reactions under normal conditions?

Alkynes undergoes reduction using sodium in liquid ammonia to give …………

Alkynes undergoes reduction using Lindlar’s catalyst to give ………….

The correct trend of acidic nature of the following alkynes isA. `CH-=CH gt CH_(3) - C-=CH gt CH_(3) C -=C CH_(3)`B. `CH_(3)-C -=CH gt CH -= CH gt CH_(3) C -= C CH_(3)`C. `CH_(3)C -= C CH_(3) gt CH_(3 - C-=CH gt CH -= CH`D. `CH-=CH gt CH_(3)C -= C CH_(3) gt CH_(3) C -=CH`

Give reason: Acidic nature of alkynes is used to distinguish between terminal and nonterminal alkynes.

Fine the odd one out: (a) Benzene(b) Ethane(c) Ethene (d) Propyne

Bond length of ethane (I), ethene (II), acetylene (III) and benzene (IV) follows the orderA. `I gt II gt III gt IV `B. `I gt II gt IV gt III`C. `I gt IV gt II gt III`D. `III gt IV gt II gt I`

3-Hexyne reacts with Na/liq. `NH_(3)` to produceA. cis-3-HexeneB. trans-3-HexeneC. 3-HexylamineD. 2-Hexylamine

Benzene and naphthalene form an ideal solution at room temperature. For this process,the true statement(s) is (are)A. `DeltaH` is positiveB. `DeltaS_("system")` is positiveC. `DeltaS("surroundings")=0`D. `DeltaH=0`

Some meta-directing substituents in aromatic substitution are given which one is the most deactivating?A. `-NO_(2)`B. `-C-=N`C. `-SO_(3)H`D. `-COOH`

Some meta-directing substituents in aromatic substitution are given. Which one is most deactivating? (a) – COOH (b) – NO2(c) – C N (d) – SO3H

Some meta-directing substituents in aromatic substitution are given.Which one is most deactivating ?A. `-COOH`B. `-NO_2`C. `-C-=N`D. `-SO_3H`