The group that activates benzene ring towards electrophilic substitution reaction is-
1. | OH | 2. | NO2 |
3. | CN | 4. | COOH |
Select the correct option based on statements below:
Assertion (A): | -OH, -OCH3 groups are o, p-directing. |
Reason (R): | Ring is activated by the resonance effect of -OH, -OCH3 groups. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
An appropriate set of reactants for the preparation of 1-methoxy-4-nitrobenzene is/are :
1. | |
2. | |
3. | |
4. |
Select the correct option based on statements below:
Assertion (A): | Phenol forms 2,4,6-tribromophenol on treatment with Br2 in carbon disulphide at 273K. |
Reason (R): | Bromine polarises in carbon disulphide. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
The alkoxy group in aryl alkyl ethers activate the benzene ring towards -
1. Nucleophilic addition reaction
2. Electrophilic addition reaction
3. Nucleophilic substitution reaction
4. Electrophilic substitution reaction
Select the correct option based on statements below:
Assertion (A): | Like the bromination of benzene, bromination of phenol is carried out in the presence of Lewis acid. |
Reason (R): | Lewis acid polarizes the bromine molecule. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |
Select the correct option based on the statements below:
Assertion (A): | Phenols give o-and p-nitrophenol on nitration with conc. HNO3 and H2SO4 mixture. |
Reason (R): | —OH group in phenol is o-, p-directing. |
1. | Both (A) and (R) are true, and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |