Amines And Amides

Question 1

Give two ways amines can by prepared

Answer 1

By nucleophillic substitution

Reduction from nitriles

Question 2

What type of amine does reduction of nitrile produce

Answer 2

A primary amine

Question 3

Give the equation for the production of an primary amine and how it’s formed

Answer 3

R-X+2NH3->R-NH2+NH4(+)X-

They will form of ammonia and a haloalkane are mixed in 1:1 ratio

Question 4

How are secondary amines formed and give the equation

Answer 4

They can be formed by reacting haloalkane and ammonia in a 2:1 ratio (2R-X+NH3->R-NH-R+2HX)

Or reacting a haloalkane with a primary
amine in a1:1 ratio

R1-X+ R2-NH2->R1-NH-R2+HX

Question 5

How are tertiary amines formed and give the equation

Answer 5

They can be formed by reacting haloalkanes and ammonia in a3:1 ratio
(3R-X + NH3->R3N+3HX)

Or by reacting a secondary amine in a 1:1 ratio

(R1-X+R2-NH-R3->R1-R2-R3N + HX

Question 6

How are quaternary ammonium salt formed and give the equation

Answer 6

They can formed by reacting haloalkanes and ammonia in a4:1 ratio
(4R-X+NH3->[R4N]+X- + 3HX)

Or by reacting tertiary amines and haloalkanes in a1:1 ratio

(R1-X +R2R3R4N->[R1R2R3R4N]+X-

Question 7

Give the equation for the reduction of nitriles to form primary amines and name the reducing agent

Answer 7

R-CN+4[H]->R-CH2NH2

LiALH4

Question 8

What happens when amines are reacted with acids

Answer 8

Alkyl ammonium salts are produced

Question 9

What determines the strength of a the base

Answer 9

The availability of the lone pair

Question 10

Give the base order strength in from weakest to strongest state the reason for the increase

Answer 10

Primary amine
Secondary amine
Tertiary amine

The reason for increase in base strength is due to the increase in the number of akyl groups attached on the N atom which increases the electron density on it and it increases the availability of the lone pair

Question 11

What happens when alkyl ammonium salts are reacted with alkalis and give the equation

Answer 11

They form amines nacl and water

Primary ammonium salts-R1-NH3Cl+NAOH->R1-Nh2+NaCl+H2O

Secondary ammonium salts-R1R2-NH2Cl+NaOh->R1R2-NH+NaCl+H2O

Tertiary ammonium salts:R1R2R3-NHCl+NaoH->R1R2R3-N+Nacl+H2O

Question 12

What are quaternary ammonium salts used as

Answer 12

Cationic surfactants

Question 13

What are amino acids

Answer 13

Molecules that contain an amine group and carboxylic acid group

Question 14

What occurs when amino acids react with sodium hydroxide and give the equation

Answer 14

A carboxylate salt and water are formed

R-CHNH2COOH+NaoH->RCHNH2COONa+H2O

Question 15

In high ph what form do amino acids exist and what firm in low ph do they exist as

Answer 15

In anionic form(negative form)

In cationic form in low ph(positive form)

Question 16

What is a zwitterion

Answer 16

When amino acids undergo an acid base reaction with itself as they have proton donating and accepting group

Question 17

What is the primary structure of a protein

Answer 17

The sequence of amino acids in a protein

Question 18

What two things can be formed in the secondary structure

Answer 18

A helix
Beta pleated sheets

They occur when hydrogen bonds occur between the hydrogen atom on a peptide link can form a bond with a nitrogen or oxygen atom

Question 19

What 3 bonds occur in the tertiary structure of a protein

Answer 19

Hydrogen bonding

Ionic bonding- occurs between -NH3 and COO

Covalent bond A

Question 20

How does tertiary structure form

Answer 20

The form as a result of the interaction between amino acids and it influence the overall shape of a protein

Question 21

How does DNA form

Answer 21

By condensation polymerisation

One oh groups of phosphate

Question 22

Why bases like phenylamine(contains benzene ring) considered weak based

Answer 22

As the lone pair from the amine group overlaps into the delocalised system so is less available as a result

Question 23

How can amino acids be located on w chromatrogran

Answer 23

Using uv light and ninhdydrin