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CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317400 How many of the following species can act as a Lewis acid?
${BCl}_{3}, {CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ . ${({CH}_{3})}_{3} C, {SiCl}_{4}, {AlCl}_{3}$

1 1

2 2

3 3

4 4

Explanation:

${CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ act as nucleophiles (i.e., Lewis base) while ${BCl}_{3}$ , tert-butylcarbocation $[{({CH}_{3})}_{3} C^{+}], {SiCl}_{4}$ and ${AlCl}_{3}$ act as Lewis acid.

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317401 An example of nucleophile is

1

C_{2} H_{6}

2

C_{2} H_{2}

3

H^{+}

4

R^{+}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317402 The correct order of nucleophilicity is

1

I^{-} > {Br}^{-} > {Cl}^{-} > F^{-}

2

I^{-} > {Cl}^{-} > {Br}^{-} > F^{-}

3

F^{-} > {Cl}^{-} > {Br}^{-} > I^{-}

4

{Cl}^{-} > {Br}^{-} > F^{-} > I^{-}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317403 Among the following, the one that is not a nucleophile is

1

{NH}_{3}

2

O H^{⊖}

3

R O R

4

{AlCl}_{3}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317404 The correct nucleophilicity order is

1

{CH}_{3}^{-} < {NH}_{2}^{-} < {HO}^{-} < F^{-}

2

{CH}_{3}^{-} ≃ {NH}_{2}^{-} > {HO}^{-} ≃ F^{-}

3

{CH}_{3}^{-} > {NH}_{2}^{-} > {HO}^{-} > F^{-}

4

{NH}_{2}^{-} > F^{-} > {HO}^{-} > {CH}_{3}^{-}

Explanation:

Nucleophilicity increases with the decrease in electronegativity of the central atom. Since electronegativity follows the order : $F > O > N > C$ ; nucleophilicity of the concerned group will follow the reverse order i.e., ${CH}_{3}^{-} > {NH}_{2}^{-} > {OH}^{-} > F^{-}$ .

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317400 How many of the following species can act as a Lewis acid?
${BCl}_{3}, {CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ . ${({CH}_{3})}_{3} C, {SiCl}_{4}, {AlCl}_{3}$

1 1

2 2

3 3

4 4

Explanation:

${CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ act as nucleophiles (i.e., Lewis base) while ${BCl}_{3}$ , tert-butylcarbocation $[{({CH}_{3})}_{3} C^{+}], {SiCl}_{4}$ and ${AlCl}_{3}$ act as Lewis acid.

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317401 An example of nucleophile is

1

C_{2} H_{6}

2

C_{2} H_{2}

3

H^{+}

4

R^{+}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317402 The correct order of nucleophilicity is

1

I^{-} > {Br}^{-} > {Cl}^{-} > F^{-}

2

I^{-} > {Cl}^{-} > {Br}^{-} > F^{-}

3

F^{-} > {Cl}^{-} > {Br}^{-} > I^{-}

4

{Cl}^{-} > {Br}^{-} > F^{-} > I^{-}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317403 Among the following, the one that is not a nucleophile is

1

{NH}_{3}

2

O H^{⊖}

3

R O R

4

{AlCl}_{3}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317404 The correct nucleophilicity order is

1

{CH}_{3}^{-} < {NH}_{2}^{-} < {HO}^{-} < F^{-}

2

{CH}_{3}^{-} ≃ {NH}_{2}^{-} > {HO}^{-} ≃ F^{-}

3

{CH}_{3}^{-} > {NH}_{2}^{-} > {HO}^{-} > F^{-}

4

{NH}_{2}^{-} > F^{-} > {HO}^{-} > {CH}_{3}^{-}

Explanation:

Nucleophilicity increases with the decrease in electronegativity of the central atom. Since electronegativity follows the order : $F > O > N > C$ ; nucleophilicity of the concerned group will follow the reverse order i.e., ${CH}_{3}^{-} > {NH}_{2}^{-} > {OH}^{-} > F^{-}$ .

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317400 How many of the following species can act as a Lewis acid?
${BCl}_{3}, {CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ . ${({CH}_{3})}_{3} C, {SiCl}_{4}, {AlCl}_{3}$

1 1

2 2

3 3

4 4

Explanation:

${CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ act as nucleophiles (i.e., Lewis base) while ${BCl}_{3}$ , tert-butylcarbocation $[{({CH}_{3})}_{3} C^{+}], {SiCl}_{4}$ and ${AlCl}_{3}$ act as Lewis acid.

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317401 An example of nucleophile is

1

C_{2} H_{6}

2

C_{2} H_{2}

3

H^{+}

4

R^{+}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317402 The correct order of nucleophilicity is

1

I^{-} > {Br}^{-} > {Cl}^{-} > F^{-}

2

I^{-} > {Cl}^{-} > {Br}^{-} > F^{-}

3

F^{-} > {Cl}^{-} > {Br}^{-} > I^{-}

4

{Cl}^{-} > {Br}^{-} > F^{-} > I^{-}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317403 Among the following, the one that is not a nucleophile is

1

{NH}_{3}

2

O H^{⊖}

3

R O R

4

{AlCl}_{3}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317404 The correct nucleophilicity order is

1

{CH}_{3}^{-} < {NH}_{2}^{-} < {HO}^{-} < F^{-}

2

{CH}_{3}^{-} ≃ {NH}_{2}^{-} > {HO}^{-} ≃ F^{-}

3

{CH}_{3}^{-} > {NH}_{2}^{-} > {HO}^{-} > F^{-}

4

{NH}_{2}^{-} > F^{-} > {HO}^{-} > {CH}_{3}^{-}

Explanation:

Nucleophilicity increases with the decrease in electronegativity of the central atom. Since electronegativity follows the order : $F > O > N > C$ ; nucleophilicity of the concerned group will follow the reverse order i.e., ${CH}_{3}^{-} > {NH}_{2}^{-} > {OH}^{-} > F^{-}$ .

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317400 How many of the following species can act as a Lewis acid?
${BCl}_{3}, {CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ . ${({CH}_{3})}_{3} C, {SiCl}_{4}, {AlCl}_{3}$

1 1

2 2

3 3

4 4

Explanation:

${CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ act as nucleophiles (i.e., Lewis base) while ${BCl}_{3}$ , tert-butylcarbocation $[{({CH}_{3})}_{3} C^{+}], {SiCl}_{4}$ and ${AlCl}_{3}$ act as Lewis acid.

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317401 An example of nucleophile is

1

C_{2} H_{6}

2

C_{2} H_{2}

3

H^{+}

4

R^{+}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317402 The correct order of nucleophilicity is

1

I^{-} > {Br}^{-} > {Cl}^{-} > F^{-}

2

I^{-} > {Cl}^{-} > {Br}^{-} > F^{-}

3

F^{-} > {Cl}^{-} > {Br}^{-} > I^{-}

4

{Cl}^{-} > {Br}^{-} > F^{-} > I^{-}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317403 Among the following, the one that is not a nucleophile is

1

{NH}_{3}

2

O H^{⊖}

3

R O R

4

{AlCl}_{3}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317404 The correct nucleophilicity order is

1

{CH}_{3}^{-} < {NH}_{2}^{-} < {HO}^{-} < F^{-}

2

{CH}_{3}^{-} ≃ {NH}_{2}^{-} > {HO}^{-} ≃ F^{-}

3

{CH}_{3}^{-} > {NH}_{2}^{-} > {HO}^{-} > F^{-}

4

{NH}_{2}^{-} > F^{-} > {HO}^{-} > {CH}_{3}^{-}

Explanation:

Nucleophilicity increases with the decrease in electronegativity of the central atom. Since electronegativity follows the order : $F > O > N > C$ ; nucleophilicity of the concerned group will follow the reverse order i.e., ${CH}_{3}^{-} > {NH}_{2}^{-} > {OH}^{-} > F^{-}$ .

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317400 How many of the following species can act as a Lewis acid?
${BCl}_{3}, {CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ . ${({CH}_{3})}_{3} C, {SiCl}_{4}, {AlCl}_{3}$

1 1

2 2

3 3

4 4

Explanation:

${CH}_{3} {OCH}_{3}, {NH}_{3}, {CH}_{3} OH, H_{2} O, ROH$ act as nucleophiles (i.e., Lewis base) while ${BCl}_{3}$ , tert-butylcarbocation $[{({CH}_{3})}_{3} C^{+}], {SiCl}_{4}$ and ${AlCl}_{3}$ act as Lewis acid.

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317401 An example of nucleophile is

1

C_{2} H_{6}

2

C_{2} H_{2}

3

H^{+}

4

R^{+}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317402 The correct order of nucleophilicity is

1

I^{-} > {Br}^{-} > {Cl}^{-} > F^{-}

2

I^{-} > {Cl}^{-} > {Br}^{-} > F^{-}

3

F^{-} > {Cl}^{-} > {Br}^{-} > I^{-}

4

{Cl}^{-} > {Br}^{-} > F^{-} > I^{-}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317403 Among the following, the one that is not a nucleophile is

1

{NH}_{3}

2

O H^{⊖}

3

R O R

4

{AlCl}_{3}

CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES

317404 The correct nucleophilicity order is

1

{CH}_{3}^{-} < {NH}_{2}^{-} < {HO}^{-} < F^{-}

2

{CH}_{3}^{-} ≃ {NH}_{2}^{-} > {HO}^{-} ≃ F^{-}

3

{CH}_{3}^{-} > {NH}_{2}^{-} > {HO}^{-} > F^{-}

4

{NH}_{2}^{-} > F^{-} > {HO}^{-} > {CH}_{3}^{-}

Explanation:

Nucleophilicity increases with the decrease in electronegativity of the central atom. Since electronegativity follows the order : $F > O > N > C$ ; nucleophilicity of the concerned group will follow the reverse order i.e., ${CH}_{3}^{-} > {NH}_{2}^{-} > {OH}^{-} > F^{-}$ .