131 + Interview Questions in ORGANIC-REACTION-MECHANISMS IN GENERAL AWARENESS Page 3 InterviewSolution

101.	Ketone is formed by the reactionA. (I)(i)(Q)B. (IV)(iii)(R)C. (III)(iv)(Q)D. (II)(iii)(P)
Answer» Correct Answer - A

Discussion

102.	Which of the following is non-correct for substitution reaction.A. (II)(iii)(R)B. (IV)(ii)(S)C. (III)(iv)(R)D. (IV)(iii)(P)
Answer» Correct Answer - A

Discussion

103.	The unimolecular nucleophilic substitution is represented by :A. (II),(iii),(Q)B. (I),(iv),(S)C. (IV),(iv),(Q)D. (IV),(iii),(Q)
Answer» Correct Answer - D

Discussion

104.	Which of the following species is expected to have maximum enthalpy in an electrophilic aromatic substitution reaction ? A. Species (II)B. Species (III)C. Species (IV)D. Species (V)
Answer» Correct Answer - A

Discussion

105.	Chlorobenzene is o,p-directing in electrophilic substitution reaction. The directing influence is explained by :A. `+m` of PhB. `+I` of ClC. `+m` of ClD. `+I` of Ph
Answer» Correct Answer - C

Discussion

106.	Toluene is o/p orienting with respect to an electrophilic substitution reaction due toA. I effect of the methyl groupB. I as well as +m effect of the methyl groupC. hyperconjugation between the methyl group and the phenyl ringD. `+m` effect of the methyl group .
Answer» Correct Answer - C

Discussion

107.	Which of the following reactions is not an electrophilic addition reactions -A. B. C. D.
Answer» Correct Answer - C Reaction A is free radical addition and all are electrophilic addition reactions.

Discussion

108.	Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds A. 1 gt 2 gt 3 gt 4B. 4 gt 3 gt 2 gt 1C. 2 gt 1 gt 3 gt 4D. 2 gt 3 gt 1 gt 4
Answer» Correct Answer - C

Discussion

109.	Electrophilic aromatic substitution can be seen in which of the following cases ?A. B. C. D.
Answer» Correct Answer - A::B::C

Discussion

110.	Consider experimental data shown in the table : Rate of electrophilic addition on isobutylene is significantly higher than cis or trans-2-Butene chiefly due to -A. B. C. Better stabilization of positive charge acquired during formation of bromonium ion intermediate by Me-groups.D. High angle strain in the molecule.
Answer» Correct Answer - C

Discussion

111.	The order of reactivity of the following compounds in electrophilic monochlorinatic the most favorable position is A. I lt II lt IV lt IIIB. III lt IV lt I lt IIC. IV lt III lt II lt ID. III lt II lt IV lt I
Answer» Correct Answer - B

Discussion

112.	Arrange in decreasing order of reactivity with HCl : A. II gt III gt IB. III gt II gt IC. III gt I gt IID. none of the above
Answer» Correct Answer - B

Discussion

113.	Which one of following compounds undergoes `EI` reaction most readily?A. `CH_3-undersetunderset(Br)(\|)oversetoverset(CH_3)(\|)C-CH_2-CH_3`B. `CH_3-CH_2-CH_2-Br`C. `CH_3-CH_2-CH_2-I`D. `CH_3-undersetunderset(I)(\|)oversetoverset(CH_3)(\|)C-CH_2-CH_3`
Answer» Correct Answer - D

Discussion

114.	Arrange the following compounds in order of decreasing reactivity in the elimination (bimolecular ) reaction with `C_2H_5ONa` A. II gt I gt III gt IVB. IV gt III gt I gt IIC. III gt I gt II gt IVD. I gt III gt IV gt II
Answer» Correct Answer - A

Discussion

115.	Which of the following most readily undergoes `E_(2)` elimination with a strong base?A. 2-bromopentaneB. 2-bromo-2-methylbutaneC. 1-bromo-2,2dimethylpropaneD. 2-bromo-3-methylbutane
Answer» Correct Answer - B

Discussion

116.	The rate of elimination is fastest inA. `Ph-CH_2-CH_2-F`B. `Ph-undersetunderset(O)(\|\|)C-CH_2-CH_2-F`C. `Ph-O-CH_2-CH_2-F`D. `CH_3-CH_2-CH_2-F`
Answer» Correct Answer - B

Discussion

117.	Which of the following compounds can give E1cB reaction ?A. `CF_3-CHCl_2`B. `C_6H_5-undersetunderset(NO_2)(\|)CH-CH_2F`C. `CH_3-CH_2-CH_2Br`D. `C_6H_5-undersetunderset(OH)(\|)CH-CH_2-CHO`
Answer» Correct Answer - A::B::D

Discussion

118.	The alkene formed as a major product in the above elimination reaction isA. B. `CH_2=CH_2`C. D.
Answer» Correct Answer - B

Discussion

119.	The elimination reactions mainly involve three mechanism E1,E2 and E1cB. If the leaving group departs before `beta`-proton (`H^t=Theta` ion) then it is E1 mechanism. If proton is taken off first before leaving group it is E1cB mechanism.The pure E2 involves both `beta`-Hydrogen and leaving group departing simutaneously. If acidity of `beta`-Hydrogen increases and leaving group ability decreases then E1cB mechanism increases. Which of the following substrate will undergo fastest reaction through E1cB routeA. B. C. D.
Answer» Correct Answer - D `-I` and -M group increases acidic strength.

Discussion

120.	The electrophile, `E^((o+))` attacks the benzene ring to generate the intermediate `sigma`-complex. Of the following which `sigma`-complex is of lowest energy?A. B. C. D.
Answer» Correct Answer - A

Discussion

121.	The carbanion expels a leaving group LG to yield an alkene as shown above byA. E1cB mechanismB. E1 mechanismC. E2 mechanismD. Such a reaction does not take place
Answer» Correct Answer - A

Discussion

122.	An alkyl halide (X) on reaction with ethanolic sodium hydroxide forms an alkene (Y) which on further reaction with HBr gives the same alkyl halide.The alkene (Y) on reaction with HBr/ peroxide followed by reaction with Hg metal followed by reaction with HCN produces an aldehyde (Z).Z is :A. B. C. D.
Answer» Correct Answer - B::C

Discussion

123.	How many reactions will proceed through free radical addition mechanism ?
Answer» Correct Answer - 2 Only (iii) & (v)

Discussion

124.	The correct order of reactivity of alkene towards an electrophile is mentioned in :A. `CH_2=CH-Cl gt CH_2 = CH -OCH_3`B. `CH_2=CHCl lt CH_2 =C Cl_2`C. `CH_2=CH_2 gt CH_3 -CH=CH_2`D. `CH_2=CH-OCH_3 gt CH_2=CH-CH_2-OH`
Answer» Correct Answer - D

Discussion

125.	LIST-I contains reactions and LIST-II contains major products. A. P`to`1,5 , Q`to`2 , R`to`3 , S`to`4B. P`to`1,4 , Q`to`2 , R`to`4 , S`to`3C. P`to`1,4 , Q`to`1,2 , R`to`3,4 , S`to`4D. P`to`4,5 , Q`to`4 , R`to`4 , S`to`3,4
Answer» Correct Answer - B

Discussion

126.	Select the reactions in which the correct orientations have been mentioned in the major products .A. B. C. D.
Answer» Correct Answer - A::C

Discussion

127.	`CH_3-undersetunderset(O)(\|\|)C-CH_3+PhMgBrtoAoverset(H_3O^+)toBunderset(Delta)overset(H_3PO_4)toC` C is :A. `Ph-undersetunderset(O)(\|\|)C-CH_3`B. `Ph-undersetunderset(OH)(\|)oversetoverset(CH_3)(\|)C-CH_3`C. `Ph-undersetunderset(CH_3)(\|)C=CH_2`D. `Ph-undersetunderset(CH_3)(\|)CH-CH_3`
Answer» Correct Answer - C

Discussion

128.	Methane reacts with excess of chlorine is diffused sunlight to give the final product asA. ChloroformB. Methyl chlorideC. Methylene chlorideD. Carbon tetrachloride
Answer» Correct Answer - D

Discussion

129.	In the hydroboration-oxidation reaction of propene with dibroane, `H_2O_2` and NaOH, the organic compound formed is :A. `CH_3CH_2OH`B. `CH_3CHOHCH_3`C. `CH_3CH_2CH_2OH`D. `(CH_3)_3COH`
Answer» Correct Answer - C

Discussion

130.	Which is correct statement about X and Y.A. X is product of ionic reaction and Y is product of radical reactionB. X and Y both are product of ionic reactionC. X and Y both are product of radical reactionD. X is product of radical reaction and Y is product of ionic reaction
Answer» Correct Answer - A In the presence of peroxide, HBr undergoes free radical addition and HCl undergoes electrophilic addition, because of H-Cl bond have high bond energy .

Discussion

131.	Three acyclic alkenes (x,y,z) on catalytic hyrogenation give same alkane. On reaction with HCl (x,y,z) form same major tertiary halide product.Reductive ozonolysis of mixture of (x,y,z) gives a mixture of two moles of `CH_2=O` one moles of `CH_3CH=O` one mole of acetone, one mole of butanone and one mole of 2-methyl propanal, x,y and z do not have any stereoisomers. (x,y,z)`overset(H_3O^())to` addition product . The correct statement isA. All three alkenes will give 3 different major hydration productsB. Three alkenes will give same hydration major productC. Two alkenes form same product but one alkene forms different major product.D. Addition of HCl and `H_3O^()` both are following different regioselectivity.
Answer» Correct Answer - B

Discussion

Explore topic-wise InterviewSolutions in .

Ketone is formed by the reactionA. (I)(i)(Q)B. (IV)(iii)(R)C. (III)(iv)(Q)D. (II)(iii)(P)

Which of the following is non-correct for substitution reaction.A. (II)(iii)(R)B. (IV)(ii)(S)C. (III)(iv)(R)D. (IV)(iii)(P)

The unimolecular nucleophilic substitution is represented by :A. (II),(iii),(Q)B. (I),(iv),(S)C. (IV),(iv),(Q)D. (IV),(iii),(Q)

Which of the following species is expected to have maximum enthalpy in an electrophilic aromatic substitution reaction ? A. Species (II)B. Species (III)C. Species (IV)D. Species (V)

Chlorobenzene is o,p-directing in electrophilic substitution reaction. The directing influence is explained by :A. `+m` of PhB. `+I` of ClC. `+m` of ClD. `+I` of Ph

Toluene is o/p orienting with respect to an electrophilic substitution reaction due toA. I effect of the methyl groupB. I as well as +m effect of the methyl groupC. hyperconjugation between the methyl group and the phenyl ringD. `+m` effect of the methyl group .

Which of the following reactions is not an electrophilic addition reactions -A. B. C. D.

Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds A. 1 gt 2 gt 3 gt 4B. 4 gt 3 gt 2 gt 1C. 2 gt 1 gt 3 gt 4D. 2 gt 3 gt 1 gt 4

Electrophilic aromatic substitution can be seen in which of the following cases ?A. B. C. D.

The order of reactivity of the following compounds in electrophilic monochlorinatic the most favorable position is A. I lt II lt IV lt IIIB. III lt IV lt I lt IIC. IV lt III lt II lt ID. III lt II lt IV lt I

Arrange in decreasing order of reactivity with HCl : A. II gt III gt IB. III gt II gt IC. III gt I gt IID. none of the above

Which one of following compounds undergoes `EI` reaction most readily?A. `CH_3-undersetunderset(Br)(|)oversetoverset(CH_3)(|)C-CH_2-CH_3`B. `CH_3-CH_2-CH_2-Br`C. `CH_3-CH_2-CH_2-I`D. `CH_3-undersetunderset(I)(|)oversetoverset(CH_3)(|)C-CH_2-CH_3`

Arrange the following compounds in order of decreasing reactivity in the elimination (bimolecular ) reaction with `C_2H_5ONa` A. II gt I gt III gt IVB. IV gt III gt I gt IIC. III gt I gt II gt IVD. I gt III gt IV gt II

Which of the following most readily undergoes `E_(2)` elimination with a strong base?A. 2-bromopentaneB. 2-bromo-2-methylbutaneC. 1-bromo-2,2dimethylpropaneD. 2-bromo-3-methylbutane

The rate of elimination is fastest inA. `Ph-CH_2-CH_2-F`B. `Ph-undersetunderset(O)(||)C-CH_2-CH_2-F`C. `Ph-O-CH_2-CH_2-F`D. `CH_3-CH_2-CH_2-F`

Which of the following compounds can give E1cB reaction ?A. `CF_3-CHCl_2`B. `C_6H_5-undersetunderset(NO_2)(|)CH-CH_2F`C. `CH_3-CH_2-CH_2Br`D. `C_6H_5-undersetunderset(OH)(|)CH-CH_2-CHO`

The alkene formed as a major product in the above elimination reaction isA. B. `CH_2=CH_2`C. D.

The electrophile, `E^((o+))` attacks the benzene ring to generate the intermediate `sigma`-complex. Of the following which `sigma`-complex is of lowest energy?A. B. C. D.

The carbanion expels a leaving group LG to yield an alkene as shown above byA. E1cB mechanismB. E1 mechanismC. E2 mechanismD. Such a reaction does not take place

An alkyl halide (X) on reaction with ethanolic sodium hydroxide forms an alkene (Y) which on further reaction with HBr gives the same alkyl halide.The alkene (Y) on reaction with HBr/ peroxide followed by reaction with Hg metal followed by reaction with HCN produces an aldehyde (Z).Z is :A. B. C. D.

How many reactions will proceed through free radical addition mechanism ?

The correct order of reactivity of alkene towards an electrophile is mentioned in :A. `CH_2=CH-Cl gt CH_2 = CH -OCH_3`B. `CH_2=CHCl lt CH_2 =C Cl_2`C. `CH_2=CH_2 gt CH_3 -CH=CH_2`D. `CH_2=CH-OCH_3 gt CH_2=CH-CH_2-OH`

LIST-I contains reactions and LIST-II contains major products. A. P`to`1,5 , Q`to`2 , R`to`3 , S`to`4B. P`to`1,4 , Q`to`2 , R`to`4 , S`to`3C. P`to`1,4 , Q`to`1,2 , R`to`3,4 , S`to`4D. P`to`4,5 , Q`to`4 , R`to`4 , S`to`3,4

Select the reactions in which the correct orientations have been mentioned in the major products .A. B. C. D.

`CH_3-undersetunderset(O)(||)C-CH_3+PhMgBrtoAoverset(H_3O^+)toBunderset(Delta)overset(H_3PO_4)toC` C is :A. `Ph-undersetunderset(O)(||)C-CH_3`B. `Ph-undersetunderset(OH)(|)oversetoverset(CH_3)(|)C-CH_3`C. `Ph-undersetunderset(CH_3)(|)C=CH_2`D. `Ph-undersetunderset(CH_3)(|)CH-CH_3`

Methane reacts with excess of chlorine is diffused sunlight to give the final product asA. ChloroformB. Methyl chlorideC. Methylene chlorideD. Carbon tetrachloride

In the hydroboration-oxidation reaction of propene with dibroane, `H_2O_2` and NaOH, the organic compound formed is :A. `CH_3CH_2OH`B. `CH_3CHOHCH_3`C. `CH_3CH_2CH_2OH`D. `(CH_3)_3COH`

Which is correct statement about X and Y.A. X is product of ionic reaction and Y is product of radical reactionB. X and Y both are product of ionic reactionC. X and Y both are product of radical reactionD. X is product of radical reaction and Y is product of ionic reaction