323603
When a nucleophile encounters a ketone, the site of attack is
1 The oxygen atom of the carbonyl group
2 The carbon atom of the carbonyl group
3 Both the carbon and oxygen atoms, with equal probability
4 No attack occurs as ketones do not react with nucleophiles
Explanation:
Carbon atom of the carbonyl group acts as electrophile. So, nucleophile attacks on carbon atom.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323604
The order of reactivity of the following compounds with \(\mathrm{PhMgBr}\) is (I) \(\mathrm{PhCOPh}\) (II) \(\mathrm{CH}_{3} \mathrm{CHO}\) (III) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\)
1 (I) \(>\) (II) \(>\) (III)
2 (III) \(>\) (I) \(>\) (II)
3 (II) \(>\) (I) \(>\) (III)
4 (II) \(>\) (III) \(>\) (I)
Explanation:
Reaction of carbonyl compounds with \(\mathrm{PhMgBr}\) is based on electrophilicity of carbonyl group and steric crowding around it. Based on electrophilicity and crowding, \(\mathrm{CH}_{3} \mathrm{CHO}\) is most reactive. The least reactive will be \(\mathrm{PhCOPh}\) due to excessive steric crowding.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323605
Assertion : Presence of acids and bases activates carbonyl compounds for reaction. Reason : Carbonyl compounds possess positive and negative centres and provide seat for electrophilic and nucleophilic attack.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Presence of acid intensifies the partial positive charge on carbonyl carbon and hence, activates the group. Presence of base activates \(\alpha\)-methylene component of the carbonyl compounds by converting them in carbanions. \(\mathrm{RCH}_{2} \mathrm{CHO}+: \mathrm{B}^{-} \rightarrow \mathrm{R} \overline{\mathrm{C}} \mathrm{HCHO}+\mathrm{BH}\). So the option (2) is correct.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323606
Which among the following is most reactive towards nucleophilic addition?
1 \(\mathrm{FCH}_{2} \mathrm{CHO}\)
2 \(\mathrm{ClCH}_{2} \mathrm{CHO}\)
3 \(\mathrm{BrCH}_{2} \mathrm{CO}\)
4 \(\mathrm{ICH}_{2} \mathrm{CHO}\)
Explanation:
In \({\text{FC}}{{\text{H}}_{\text{2}}}{\text{CHO,}}\) fluroine is a strong electron withdrawing in nature. This make - \(\mathrm{CO}\) group more polar and makes this compound more reactive towards \(\mathrm{Nu}^{\Theta}\) addition.
323603
When a nucleophile encounters a ketone, the site of attack is
1 The oxygen atom of the carbonyl group
2 The carbon atom of the carbonyl group
3 Both the carbon and oxygen atoms, with equal probability
4 No attack occurs as ketones do not react with nucleophiles
Explanation:
Carbon atom of the carbonyl group acts as electrophile. So, nucleophile attacks on carbon atom.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323604
The order of reactivity of the following compounds with \(\mathrm{PhMgBr}\) is (I) \(\mathrm{PhCOPh}\) (II) \(\mathrm{CH}_{3} \mathrm{CHO}\) (III) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\)
1 (I) \(>\) (II) \(>\) (III)
2 (III) \(>\) (I) \(>\) (II)
3 (II) \(>\) (I) \(>\) (III)
4 (II) \(>\) (III) \(>\) (I)
Explanation:
Reaction of carbonyl compounds with \(\mathrm{PhMgBr}\) is based on electrophilicity of carbonyl group and steric crowding around it. Based on electrophilicity and crowding, \(\mathrm{CH}_{3} \mathrm{CHO}\) is most reactive. The least reactive will be \(\mathrm{PhCOPh}\) due to excessive steric crowding.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323605
Assertion : Presence of acids and bases activates carbonyl compounds for reaction. Reason : Carbonyl compounds possess positive and negative centres and provide seat for electrophilic and nucleophilic attack.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Presence of acid intensifies the partial positive charge on carbonyl carbon and hence, activates the group. Presence of base activates \(\alpha\)-methylene component of the carbonyl compounds by converting them in carbanions. \(\mathrm{RCH}_{2} \mathrm{CHO}+: \mathrm{B}^{-} \rightarrow \mathrm{R} \overline{\mathrm{C}} \mathrm{HCHO}+\mathrm{BH}\). So the option (2) is correct.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323606
Which among the following is most reactive towards nucleophilic addition?
1 \(\mathrm{FCH}_{2} \mathrm{CHO}\)
2 \(\mathrm{ClCH}_{2} \mathrm{CHO}\)
3 \(\mathrm{BrCH}_{2} \mathrm{CO}\)
4 \(\mathrm{ICH}_{2} \mathrm{CHO}\)
Explanation:
In \({\text{FC}}{{\text{H}}_{\text{2}}}{\text{CHO,}}\) fluroine is a strong electron withdrawing in nature. This make - \(\mathrm{CO}\) group more polar and makes this compound more reactive towards \(\mathrm{Nu}^{\Theta}\) addition.
323603
When a nucleophile encounters a ketone, the site of attack is
1 The oxygen atom of the carbonyl group
2 The carbon atom of the carbonyl group
3 Both the carbon and oxygen atoms, with equal probability
4 No attack occurs as ketones do not react with nucleophiles
Explanation:
Carbon atom of the carbonyl group acts as electrophile. So, nucleophile attacks on carbon atom.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323604
The order of reactivity of the following compounds with \(\mathrm{PhMgBr}\) is (I) \(\mathrm{PhCOPh}\) (II) \(\mathrm{CH}_{3} \mathrm{CHO}\) (III) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\)
1 (I) \(>\) (II) \(>\) (III)
2 (III) \(>\) (I) \(>\) (II)
3 (II) \(>\) (I) \(>\) (III)
4 (II) \(>\) (III) \(>\) (I)
Explanation:
Reaction of carbonyl compounds with \(\mathrm{PhMgBr}\) is based on electrophilicity of carbonyl group and steric crowding around it. Based on electrophilicity and crowding, \(\mathrm{CH}_{3} \mathrm{CHO}\) is most reactive. The least reactive will be \(\mathrm{PhCOPh}\) due to excessive steric crowding.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323605
Assertion : Presence of acids and bases activates carbonyl compounds for reaction. Reason : Carbonyl compounds possess positive and negative centres and provide seat for electrophilic and nucleophilic attack.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Presence of acid intensifies the partial positive charge on carbonyl carbon and hence, activates the group. Presence of base activates \(\alpha\)-methylene component of the carbonyl compounds by converting them in carbanions. \(\mathrm{RCH}_{2} \mathrm{CHO}+: \mathrm{B}^{-} \rightarrow \mathrm{R} \overline{\mathrm{C}} \mathrm{HCHO}+\mathrm{BH}\). So the option (2) is correct.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323606
Which among the following is most reactive towards nucleophilic addition?
1 \(\mathrm{FCH}_{2} \mathrm{CHO}\)
2 \(\mathrm{ClCH}_{2} \mathrm{CHO}\)
3 \(\mathrm{BrCH}_{2} \mathrm{CO}\)
4 \(\mathrm{ICH}_{2} \mathrm{CHO}\)
Explanation:
In \({\text{FC}}{{\text{H}}_{\text{2}}}{\text{CHO,}}\) fluroine is a strong electron withdrawing in nature. This make - \(\mathrm{CO}\) group more polar and makes this compound more reactive towards \(\mathrm{Nu}^{\Theta}\) addition.
323603
When a nucleophile encounters a ketone, the site of attack is
1 The oxygen atom of the carbonyl group
2 The carbon atom of the carbonyl group
3 Both the carbon and oxygen atoms, with equal probability
4 No attack occurs as ketones do not react with nucleophiles
Explanation:
Carbon atom of the carbonyl group acts as electrophile. So, nucleophile attacks on carbon atom.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323604
The order of reactivity of the following compounds with \(\mathrm{PhMgBr}\) is (I) \(\mathrm{PhCOPh}\) (II) \(\mathrm{CH}_{3} \mathrm{CHO}\) (III) \(\mathrm{CH}_{3} \mathrm{COCH}_{3}\)
1 (I) \(>\) (II) \(>\) (III)
2 (III) \(>\) (I) \(>\) (II)
3 (II) \(>\) (I) \(>\) (III)
4 (II) \(>\) (III) \(>\) (I)
Explanation:
Reaction of carbonyl compounds with \(\mathrm{PhMgBr}\) is based on electrophilicity of carbonyl group and steric crowding around it. Based on electrophilicity and crowding, \(\mathrm{CH}_{3} \mathrm{CHO}\) is most reactive. The least reactive will be \(\mathrm{PhCOPh}\) due to excessive steric crowding.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323605
Assertion : Presence of acids and bases activates carbonyl compounds for reaction. Reason : Carbonyl compounds possess positive and negative centres and provide seat for electrophilic and nucleophilic attack.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Presence of acid intensifies the partial positive charge on carbonyl carbon and hence, activates the group. Presence of base activates \(\alpha\)-methylene component of the carbonyl compounds by converting them in carbanions. \(\mathrm{RCH}_{2} \mathrm{CHO}+: \mathrm{B}^{-} \rightarrow \mathrm{R} \overline{\mathrm{C}} \mathrm{HCHO}+\mathrm{BH}\). So the option (2) is correct.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323606
Which among the following is most reactive towards nucleophilic addition?
1 \(\mathrm{FCH}_{2} \mathrm{CHO}\)
2 \(\mathrm{ClCH}_{2} \mathrm{CHO}\)
3 \(\mathrm{BrCH}_{2} \mathrm{CO}\)
4 \(\mathrm{ICH}_{2} \mathrm{CHO}\)
Explanation:
In \({\text{FC}}{{\text{H}}_{\text{2}}}{\text{CHO,}}\) fluroine is a strong electron withdrawing in nature. This make - \(\mathrm{CO}\) group more polar and makes this compound more reactive towards \(\mathrm{Nu}^{\Theta}\) addition.
