Define primary amine .

A primary amine is an organic compound with an -NH 2 functional group attached to an alkyl or aryl group.

What type of reaction occurs when a halogenoalkane reacts with excess hot ethanolic ammonia under pressure?

A nucleophilic substitution reaction. The lone pair on nitrogen in ammonia attacks the carbon bonded to the halogen, displacing it and forming a primary amine .

True or False? Reacting a halogenoalkane with a primary amine in ethanol under pressure produces a secondary amine.

True. The nitrogen lone pair in the primary amine acts as a nucleophile and replaces the halogen via nucleophilic substitution, giving a secondary amine.

What reagent and conditions are used to reduce a nitrile to a primary amine?

Either LiAlH 4 in dry ether or H 2 gas over a nickel catalyst . The -CN group is reduced to -CH 2 NH 2 , giving a primary amine.

The reduction of a non-substituted amide by LiAlH 4 produces a .......... . The reduction of a substituted amide produces a .......... amine.

The reduction of a non-substituted amide by LiAlH 4 produces a primary amine . The reduction of a substituted amide produces a secondary amine.

Define secondary amine .

A secondary amine is an organic compound in which two alkyl or aryl groups are attached to an -NH group.

True or False? A nitrile can be reduced to a primary amine using LiAlH 4 in dry ether.

True. LiAlH 4 in dry ether reduces the -CN group to -CH 2 NH 2 , forming a primary amine. H 2 over a nickel catalyst is an alternative route.

Why must excess ammonia be used when producing a primary amine from a halogenoalkane?

Excess ammonia drives the reaction toward the primary amine product. Without excess, the primary amine formed can act as a nucleophile and react further with the halogenoalkane to give secondary and tertiary amines.

Primary amines can be formed by .......... of amides using LiAlH 4 or by .......... of nitriles using H 2 and a nickel catalyst.

Primary amines can be formed by reduction of amides using LiAlH 4 or by reduction of nitriles using H 2 and a nickel catalyst.

An amide is an organic compound containing the -CONR 2 functional group, formed by a condensation reaction between an acyl chloride and ammonia or an amine.

What type of reaction forms an amide from an acyl chloride and ammonia?

A condensation reaction . The two molecules join together and a small molecule, HCl , is eliminated.

True or False? Reacting an acyl chloride with a primary amine produces a non-substituted amide.

False. Reacting an acyl chloride with a primary or secondary amine produces a substituted amide . A non-substituted amide is produced when ammonia is used instead.

Why is carboxylic acid a less effective reagent than acyl chloride for making amides?

Carboxylic acids are less reactive than acyl chlorides, so the reaction is slower and does not go to completion. Acyl chlorides give a faster, more complete reaction.

In a condensation reaction between an acyl chloride and ammonia, the two molecules join and eliminate .......... . The product is a .......... amide.

In a condensation reaction between an acyl chloride and ammonia, the two molecules join and eliminate HCl . The product is a non-substituted amide.

True or False? The carbonyl carbon in an acyl chloride is electron-rich, making it susceptible to nucleophilic attack.

False. The chlorine atom is electronegative and withdraws electron density from the carbonyl carbon, making it electron-deficient and susceptible to nucleophilic attack.

Which part of the ammonia or amine molecule acts as the nucleophile in amide formation?

The lone pair of electrons on the nitrogen atom acts as the nucleophile, attacking the electron-deficient carbonyl carbon of the acyl chloride.

Define condensation reaction .

A condensation reaction is a reaction in which two organic molecules join together and eliminate a small molecule such as HCl or H 2 O in the process.

An amide can also be formed from the condensation reaction between a .......... and ammonia or an amine, although this reaction is slower and does not go to .......... .

An amide can also be formed from the condensation reaction between a carboxylic acid and ammonia or an amine, although this reaction is slower and does not go to completion .

Define base (in the context of amines) .

A base is a species that can donate its lone pair of electrons to form a dative covalent bond with an electron-deficient species such as a proton (H + ).

How does an alkyl group affect the basicity of an amine?

Alkyl groups have a positive inductive effect , donating electron density to the nitrogen atom. This makes the lone pair more available for dative covalent bonding, increasing the basicity of the amine.

True or False? Phenylamine is a stronger base than ethylamine.

False. Phenylamine is a weaker base than ethylamine. The benzene ring delocalises the lone pair on nitrogen, making it less available for dative covalent bonding with a proton.

Why does delocalisation of the nitrogen lone pair into a benzene ring decrease basicity?

When the lone pair overlaps with the conjugated system of the benzene ring, it becomes delocalised and less readily available to form a dative covalent bond with a proton, making the amine a weaker base.

Ammonia reacts with dilute hydrochloric acid to form .......... . In this reaction, ammonia acts as a .......... by donating its lone pair.

Ammonia reacts with dilute hydrochloric acid to form NH 4 + Cl - . In this reaction, ammonia acts as a base by donating its lone pair.

True or False? A more readily available lone pair on the nitrogen atom results in a stronger base.

True. The more readily available the lone pair is for dative covalent bonding with a proton, the stronger the base.

What is the role of the nitrogen lone pair when an amine acts as a base?

The lone pair on the nitrogen atom is donated to form a dative covalent bond with a proton (H + ). This is the defining feature of basic behaviour in amines.

Define positive inductive effect .

The positive inductive effect is the donation of electron density through sigma bonds toward an atom, as seen with alkyl groups attached to nitrogen in amines, increasing the availability of the nitrogen lone pair.

In phenylamine, the lone pair on nitrogen becomes .......... into the benzene ring. This makes the lone pair .......... available for bonding with a proton.

In phenylamine, the lone pair on nitrogen becomes delocalised into the benzene ring. This makes the lone pair less available for bonding with a proton.

A LevelChemistryCambridge (CIE)Flashcards34. Nitrogen CompoundsPrimary & Secondary Amines

Primary & Secondary Amines (Cambridge (CIE) A Level Chemistry): Flashcards

Exam code: 9701

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Cards in this collection (27)

Define primary amine.
A primary amine is an organic compound with an -NH₂ functional group attached to an alkyl or aryl group.
What type of reaction occurs when a halogenoalkane reacts with excess hot ethanolic ammonia under pressure?
A nucleophilic substitution reaction. The lone pair on nitrogen in ammonia attacks the carbon bonded to the halogen, displacing it and forming a primary amine.
True or False?
Reacting a halogenoalkane with a primary amine in ethanol under pressure produces a secondary amine.
True.
The nitrogen lone pair in the primary amine acts as a nucleophile and replaces the halogen via nucleophilic substitution, giving a secondary amine.
What reagent and conditions are used to reduce a nitrile to a primary amine?
Either LiAlH₄ in dry ether or H₂ gas over a nickel catalyst. The -CN group is reduced to -CH₂NH₂, giving a primary amine.
The reduction of a non-substituted amide by LiAlH₄ produces a ........... The reduction of a substituted amide produces a .......... amine.
The reduction of a non-substituted amide by LiAlH₄ produces a primary amine. The reduction of a substituted amide produces a secondary amine.
Define secondary amine.
A secondary amine is an organic compound in which two alkyl or aryl groups are attached to an -NH group.
True or False?
A nitrile can be reduced to a primary amine using LiAlH₄ in dry ether.
True.
LiAlH₄ in dry ether reduces the -CN group to -CH₂NH₂, forming a primary amine. H₂ over a nickel catalyst is an alternative route.
Why must excess ammonia be used when producing a primary amine from a halogenoalkane?
Excess ammonia drives the reaction toward the primary amine product. Without excess, the primary amine formed can act as a nucleophile and react further with the halogenoalkane to give secondary and tertiary amines.
Primary amines can be formed by .......... of amides using LiAlH₄ or by .......... of nitriles using H₂ and a nickel catalyst.
Primary amines can be formed by reduction of amides using LiAlH₄ or by reduction of nitriles using H₂ and a nickel catalyst.
Define amide.
An amide is an organic compound containing the -CONR₂ functional group, formed by a condensation reaction between an acyl chloride and ammonia or an amine.
What type of reaction forms an amide from an acyl chloride and ammonia?
A condensation reaction. The two molecules join together and a small molecule, HCl, is eliminated.
True or False?
Reacting an acyl chloride with a primary amine produces a non-substituted amide.
False.
Reacting an acyl chloride with a primary or secondary amine produces a substituted amide. A non-substituted amide is produced when ammonia is used instead.
Why is carboxylic acid a less effective reagent than acyl chloride for making amides?
Carboxylic acids are less reactive than acyl chlorides, so the reaction is slower and does not go to completion. Acyl chlorides give a faster, more complete reaction.
In a condensation reaction between an acyl chloride and ammonia, the two molecules join and eliminate ........... The product is a .......... amide.
In a condensation reaction between an acyl chloride and ammonia, the two molecules join and eliminate HCl. The product is a non-substituted amide.
True or False?
The carbonyl carbon in an acyl chloride is electron-rich, making it susceptible to nucleophilic attack.
False.
The chlorine atom is electronegative and withdraws electron density from the carbonyl carbon, making it electron-deficient and susceptible to nucleophilic attack.
Which part of the ammonia or amine molecule acts as the nucleophile in amide formation?
The lone pair of electrons on the nitrogen atom acts as the nucleophile, attacking the electron-deficient carbonyl carbon of the acyl chloride.
Define condensation reaction.
A condensation reaction is a reaction in which two organic molecules join together and eliminate a small molecule such as HCl or H₂O in the process.
An amide can also be formed from the condensation reaction between a .......... and ammonia or an amine, although this reaction is slower and does not go to .......... .
An amide can also be formed from the condensation reaction between a carboxylic acid and ammonia or an amine, although this reaction is slower and does not go to completion.
Define base (in the context of amines).
A base is a species that can donate its lone pair of electrons to form a dative covalent bond with an electron-deficient species such as a proton (H⁺).
How does an alkyl group affect the basicity of an amine?
Alkyl groups have a positive inductive effect, donating electron density to the nitrogen atom. This makes the lone pair more available for dative covalent bonding, increasing the basicity of the amine.
True or False?
Phenylamine is a stronger base than ethylamine.
False.
Phenylamine is a weaker base than ethylamine. The benzene ring delocalises the lone pair on nitrogen, making it less available for dative covalent bonding with a proton.
Why does delocalisation of the nitrogen lone pair into a benzene ring decrease basicity?
When the lone pair overlaps with the conjugated system of the benzene ring, it becomes delocalised and less readily available to form a dative covalent bond with a proton, making the amine a weaker base.
Ammonia reacts with dilute hydrochloric acid to form ........... In this reaction, ammonia acts as a .......... by donating its lone pair.
Ammonia reacts with dilute hydrochloric acid to form NH₄⁺Cl^-. In this reaction, ammonia acts as a base by donating its lone pair.
True or False?
A more readily available lone pair on the nitrogen atom results in a stronger base.
True.
The more readily available the lone pair is for dative covalent bonding with a proton, the stronger the base.
What is the role of the nitrogen lone pair when an amine acts as a base?
The lone pair on the nitrogen atom is donated to form a dative covalent bond with a proton (H⁺). This is the defining feature of basic behaviour in amines.
Define positive inductive effect.
The positive inductive effect is the donation of electron density through sigma bonds toward an atom, as seen with alkyl groups attached to nitrogen in amines, increasing the availability of the nitrogen lone pair.
In phenylamine, the lone pair on nitrogen becomes .......... into the benzene ring. This makes the lone pair .......... available for bonding with a proton.
In phenylamine, the lone pair on nitrogen becomes delocalised into the benzene ring. This makes the lone pair less available for bonding with a proton.

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