Assertion: Phenol is more reactive than benzene towards electrophilic reactions. Reason : The +R effect of OH group increases the electron density on

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Assertion: Phenol is more reactive than benzene towards electrophilic reactions. Reason : The +R effect of ... D. A is incorrect but R is correct

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Description : Phenol is more reactive than benzene towards electrophilic substitution reaction. In case of Phenol, the intermediate carbocation is more resonance st

Last Answer : Phenol is more reactive than benzene towards electrophilic substitution reaction. In case of Phenol, the ... D. A is incorrect but R is correct

Description : How an — OH group attached to carbon in the benzene ring activates benzene towards electrophilic substitution ?

Last Answer : The lone pair of electrons present on oxygen atom enter into resonance with the benzene ring. As a result, the electron density becomes higher at o- and p- position and due to higher electron density, the ring gets activated towards electrophilic substitution.

Description : 40. Among the following compounds the one that is most reactive towards electrophilic nitration is: (1) Benzene (2) Benzoic acid (3) Nitrobenzene (4) Toluene

Last Answer : Toluene

Description : (A) Ethyl chloride is more reactive than vinyl chloride towards nucleophilic substitution reactions. (R) Vinyl chloride is `+I` electron pushing group

Last Answer : (A) Ethyl chloride is more reactive than vinyl chloride towards nucleophilic substitution reactions. (R) Vinyl ... A) is incorrect but (R) is correct.

Description : Phenol is an ortho-para director because the hydroxyl group : (a) donates electrons that increase electron density at ortho and para positions favoring nucleophilic attack. (b) donates ... para positions and attracts electrons away from meta positions favoring electrophilic attack on the ring.

Last Answer : donates electrons that increase electron density at ortho and para positions favoring electrophilic attack.

Description : Which of the following statements correctly describes the general reactivity of alkynes? (a) An alkyne is an electron-rich molecule and therefore reacts as a nucleophile. (b) The σ bonds ... fail to undergo electrophilic addition reactions. (d) Alkynes are generally more reactive than alkenes.

Last Answer : Alkynes are generally more reactive than alkenes.

Description : Statement I: In strongly acidic solutions , anline becomes more reactive towards electrophilic reagents Statement II: The amino group being completely

Last Answer : Statement I: In strongly acidic solutions , anline becomes more reactive towards electrophilic reagents ... Assertion is false but Reason is true.

Description : Which of the following compounds reacts least rapidly in electrophilic substitution reactions? (a) Nitrobenzene (b) Phenol (c) Bromobenzene (d) Toluene

Last Answer : Nitrobenzene

Description : Which one of the following is most reactive towards electrophilic attack?

Last Answer : Which one of the following is most reactive towards electrophilic attack? A. B. C. D.

Description : Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?

Last Answer : Ans. Due to the presence of an electron cloud containing 6 pi electrons above and below the plane of the ring, benzene is a source of electrons. Consequently, it attracts ... . As a result, benzene undergoes electrophilic substitution reactions easily and nucleophilic substitution with difficulty.

Description : Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH

Last Answer : Benzene + Br2/FeBr3

Description : What purpose does FeCl3 serve in the electrophilic aromatic substitution reaction between chlorine and benzene? (a) It serves as a radical initiator to produce the chlorine radical needed to propagate the ... by reacting with the Cl2 and thereby activates it toward attack by benzene's π electrons.

Last Answer : It serves as a Lewis acid catalyst by reacting with the Cl2 and thereby activates it toward attack by benzene’s π electrons.

Description : Which of the following reactions does not produce benzene as one of the products? (a) Treating benzenediazonium chloride with H3PO2 (b) Distilling phenol with zinc dust (c) Fusing sodium benzoate with NaOH (d) Fusing sodium benzenesulfonate with NaOH

Last Answer : Fusing sodium benzenesulfonate with NaOH

Description : (A) Cation carriers, e.g., `H-Br,Cl-OH` and `Br-Br` and oxidising agents such as `O_(3)` and `R-O-O-R`, etc. act as electrophilic reagents. (R) Electr

Last Answer : (A) Cation carriers, e.g., `H-Br,Cl-OH` and `Br-Br` and oxidising agents such as `O_(3)` and ... incorrect. D. IF (A) is incorrect but (R) is correct.

Description : Assertion: (A) Ethers are relatively inert when compared to `C_(2)H_(5)OH` Reason (R): The hybridization of C and O in `CH_(3)-O-CH_(3) is SP^(3)`

Last Answer : Assertion: (A) Ethers are relatively inert when compared to `C_(2)H_(5)OH` Reason (R): The hybridization of ... R is false D. A is false but R is true

Description : Benzene reacts with concentrated HNO3 in the presence of concentrated H2SO4 to give nitrobenzene. This reaction is an example of (a) Electrophilic addition (b) Nucleophilic addition (c) Electrophilic substitution (d) Nucleophilic substitution

Last Answer : Electrophilic substitution

Description : Benzene reacts with concentrated HNO3 in the presence of concentrated H2SO4 to give nitrobenzene. This reaction is an example of (a) Electrophilic addition (b) Nucleophilic addition (c) Electrophilic substitution (d) Nucleophilic substitution

Last Answer : Electrophilic substitution

Description : Which of the following is not a correct statement about the electrophilic substitution mechanism of benzene? (a) Benzene functions as a nucleophile. (b) Formation of a carbocation intermediate is the ... hybridized carbon in the ring. (d) The addition product is a frequently observed minor product.

Last Answer : The addition product is a frequently observed minor product.

Description : Assertion :- Entropy of system increases for a spontaneous reactions. Reason :- Enthalpy of reaction always decreases for spontaneous reaction.

Last Answer : Assertion :- Entropy of system increases for a spontaneous reactions. Reason :- Enthalpy of reaction ... D. If both Assertion & Reason are false.

Description : Assertion :- In a redox reaction, the oxidation number of the oxidant decreases while that of reductant increases. Reason :- Oxidant gains electron(s)

Last Answer : Assertion :- In a redox reaction, the oxidation number of the oxidant decreases while that of reductant ... D. If both Assertion & Reason are False.

Description : Assertion (A): May endothermic reactions that are not spontaneous at room temperature become spontaneous at high temperature. Reason (R ) : Entropy of

Last Answer : Assertion (A): May endothermic reactions that are not spontaneous at room temperature become spontaneous ... . If both Assertion & Reason are false.

Description : Assertion `(A) : K-` shell electron capture is detected by analyzing the wavelength of `X-` ray emitted. Reason `(R):` The wavelength of the `X-` ray

Last Answer : Assertion `(A) : K-` shell electron capture is detected by analyzing the wavelength of `X-` ray emitted. ... D. If both (A) and (R ) are incorrect.

Description : Why do aldehydes undergo nucleophilic addition reactions while esters undergo nucleophilic acyl substitution reactions? (a) The carbonyl carbon of an ester is more electrophilic than that of an aldehyde. (b) ... adds to an aldehyde, neither H− nor R− can be eliminated since they are strongly basic

Last Answer : Once the nucleophile adds to an aldehyde, neither H− nor R− can be eliminated since they are strongly basic

Description : Assertion : Phenol has lower boiling point then water Reason : Water forms more number of hydrogen bonds

Last Answer : Assertion : Phenol has lower boiling point then water Reason : Water forms more number of hydrogen ... false D. Assertion is false, Reason is true

Description : Which of the following halogen acids is most reactive towards the given reaction ? `R-O-R overset(HX)rarr`

Last Answer : Which of the following halogen acids is most reactive towards the given reaction ? `R-O-R overset(HX)rarr` A. HCl B. HI C. HBr D. Equally reactive

Description : Assertion (A): o-phenol sulphonic acid on heating at `100^(@)C` changes to p-phenol sulphonic acid. Reason : Sulphonation of phenol is a reversible pr

Last Answer : Assertion (A): o-phenol sulphonic acid on heating at `100^(@)C` changes to p-phenol sulphonic acid. ... in correct D. A is incorrect but R is correct

Description : Aryl halides are less reactive towards nucleophilic substitution as compared to alkyl halides due to (a) Inductive effect (b) Resonance stabilization (c) Tautomerism (d) Stereoisomerism

Last Answer : Resonance stabilization

Description : Arrange the following compound in reactivity towards EAS (Electrophilic aromatic substitution) reaction ?

Last Answer : Arrange the following compound in reactivity towards EAS (Electrophilic aromatic substitution) reaction ? A. `A gt B gt ... A` D. `C gt B gt D gt A`

Description : Among the following compounds, the decreasing order of reactivity towards electrophilic substitution is :

Last Answer : Among the following compounds, the decreasing order of reactivity towards electrophilic substitution is : ... C. `IVgtIgtIIgtIII` D. `IIIgtIgtIIgtIV`

Description : Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:

Last Answer : Identify the correct order of reactivity in electrophilic substitution reactions of the following ... C. `IIgtIgtIIIgtIV` D. `IIgtIIIgtIgtIV`

Description : Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds :

Last Answer : Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds : ... ` C. `2gt1gt3gt4` D. `2gt3gt1gt4`

Description : Anthracene undergoes electrophilic substitution reactions mainly at (a) C-1 (b) C-2 (c) C-9 (d) C-1 and C-2

Last Answer : C-9

Description : In electrophilic aromatic substitution reactions a chlorine substituent __________. (a) is a deactivator and a m-director (b) is a deactivator and an o,p-director (c) is an activator and a m-director (d) is an activator and an o,p-director

Last Answer : is a deactivator and an o,p-director

Description : Which of the following characterizes the reactions of aldehydes and ketones? (a) electrophilic addition (b) electrophilic substitution (c) nucleophilic acyl substitution (d) nucleophilic addition; free radical addition

Last Answer : nucleophilic addition; free radical addition

Description : Alkyl halides undergo (a) Electrophilic substitution reactions (b) Electrophilic addition reactions (c) Nucleophilic substitution reactions (d) Nucleophilic addition reactions

Last Answer : Nucleophilic substitution reactions

Description : Assertion (A): The development of agriculture and industry leads to the development of tertiary sector. Reason (R): As the agriculture and industrial sectors develop, the demand for storage, transport, banking, insurance, etc, increases ... A. (c) A is true but R is false. (d) Both A & R are false.

Last Answer : (a) Both A & R are true and R is the correct explanation of A

Description : Howmany of the following compounds are dissolve in aqeous solution of `NaOH` (1) Phenol (2) p-cresol (3) Benzoic acid (4) Benzene sulphonic acid (5) A

Last Answer : Howmany of the following compounds are dissolve in aqeous solution of `NaOH` (1) Phenol (2) p-cresol ... P-toluedine (7) Picric acid (8) Squaric acid

Description : Benzene diazonium chloride on reaction with phenol in a basic medium gives:

Last Answer : Benzene diazonium chloride on reaction with phenol in a basic medium gives: A. benzene B. chlorobenzene C. diphenyl ether D. p-hydroxy azobenzene

Description : Caprolactam, a raw material for the manufacture of nylon-6, isproduced from (A) Phenol (B) Naphthalene (C) Benzene (D) Pyridine

Last Answer : (C) Benzene

Description : Pick out the wrong statement. (A) For the manufacture of styrene, the major raw materials are benzene and ethylene (B) One important copolymer of styrene is SBR, which is widely ... D) Phenol manufacture by chlorobenzene-caustic process is competitive even when low cost chlorine is not available

Last Answer : (D) Phenol manufacture by chlorobenzene-caustic process is competitive even when low cost chlorine is not available

Description : . Main constituents of Benzol are (A) Benzene, toluene & xylene (B) Tar & creosote (C) Ammonia & phenol (D) Anthracene & phenol

Last Answer : (A) Benzene, toluene & xylene

Description : Benzenediazonium chloride reacts with hypophosphorus acid to form : (a) Phenol (b) Benzaldehyde (c) Aniline (d) Benzene

Last Answer : Benzene

Description : Iodobenzene can be prepared by (a) treating chlorobenzene with I2 using FeCl3 catalyst. (b) treating phenol with I2 in NaOH solution. (c) treating benzenediazonium chloride with KI (d) treating benzene with CH3I using AlCl3 catalyst

Last Answer : treating benzenediazonium chloride with KI

Description : Benzenediazonium chloride reacts with warm water to give (a) Aniline (b) Phenol (c) Benzene (d) Chlorobenzene

Last Answer : Phenol

Description : Phenol on distillation with Zinc dust gives (a) Phenylzinc (b) Benzene (c) Cyclohexanone (d) Benzoic acid

Last Answer : Benzene

Description : Acetone is produced by catalytic dehydrogenation of (A) Phenol (B) Naphthalene (C) Isopropanol (D) Ethyl benzene

Last Answer : (C) Isopropanol

Description : Dehydrogenation of ethyl benzene produces (A) Styrene (B) Naphthalene (C) Phenol (D) Benzoic acid

Last Answer : (A) Styrene

Description : __________ is produced by the dehydrogenation of ethyl benzene. (A) Styrene (B) Ethyl alcohol (C) Cumene (D) Phenol

Last Answer : (A) Styrene

Description : Caprolactam (a raw material for nylon-6 manufacture) is produced from (A) Phenol (B) Naphthalene (C) Benzene (D) Pyridine

Last Answer : (C) Benzene

Description : Catalytic oxidation of toluene produces (A) Styrene (B) Phenol (C) Benzene (D) Tri-nitro-toluene

Last Answer : (B) Phenol