Amines, Amides and Hydrolysis

Question 1

What happens when an anime reacts with an acid?

What kind of reaction is it?

Answer 1

SALTS, you neutralise the amine by reacting it with an acid to make AMMONIUM SALT.

It’s an addition reaction.

Question 2

What’s the difference between an amide and an amine?

Answer 2

Amides contain -CONH2 (a carbonyl group)

Amines have -NH2 along with an R group

Question 3

How do you make an amide from an amine?

Answer 3

Acylation, where an Acyl group (R-C=O) is substituted for a hydrogen atom on an amine.

The amide given is called an N-SUBSTITUTED amide.

Reacting Acyl chloride with an amine gives HCL and an amide, the HCL will the react with any excess amine to form a salt.

Question 4

What do you get when you hydrolyse an amide with an acid?

Answer 4

A CARBOXYLIC ACID and an AMMONIUM SALT.

Question 5

What do you get when you hydrolyse an amide with an alkali?

Answer 5

CARBOXYLATE ION and AMMONIA GAS (NH3)

Question 6

Why is an amine a base?

Answer 6

It has a lone pair of electrons, so they accept protons, and form a dative covalent bond with a H+ ion

Question 7

What happens when you hydrolyse an ester with an acid?

Answer 7

You get a CARBOXYLIC ACID and an ALCOHOL.

Question 8

What happens when you hydrolyse an ester with an alkali?

Answer 8

CARBOXYLIC ACID SALT and an ALCOHOL

Question 9

What’s the point in recrystallising?

Answer 9

To purify a product

Question 10

Describe how you recrystallise something

Answer 10

1. Add very hot solvent to the impure solid until it JUST dissolves
2. This gives a SATURATED solution of the impure product
3. Leave it to cool down slowly, crystals of the product will form
4. The impurities stay in solution
5. Remove the crystals by filtration and wash them in ice cold solvent

Question 11

Why is the choice of solvent important? (In recrystallisation)

Answer 11

The solid must be very soluble in the hot solvent and nearly insoluble when the solvent is cold.