Hydrocarbons- Carboxylic acids, esters and alcohols

Question 1

Alcohols

Answer 1

Have -OH functional group (hydroxyl)
Made via hydration of alkenes
They are very flammable 
Have high boiling points
Soluble in water (hydrogen bonding)
Low volatility 
Uses includes use in alcoholic drinks, sanitisation and sterilisation

Question 2

Volatility

Answer 2

How easily a substance vaporises (evaporates)
High means evaporates easily
Low means difficult to evaporate

Question 3

Carboxylic acids

Answer 3

Have the carboxyl functional group (-COOH)
Made by oxidation of alcohols
They are acidic (approx pH 5)
Soluble in water (hydrogen bonding)
High boiling points
They are volatile
Have strong odours
Used in vinegar

Question 4

Ester reaction -

Answer 4

Alcohol + Carboxylic acid ——> Ester + Water

It is a condensation reaction

Question 5

Condensation reaction

Answer 5

When two smaller molecules join to form a larger molecule and water

Question 6

Ester properties

Answer 6

They are volatile
Have distinct “fruity smells”
Used in food flavourings as well as perfumes

Question 7

Naming esters

Answer 7

Alcohol will become prefix[yl]
Carboxylic acid will become prefix[anoate]
So - alcohol prefix[yl] Carboxylic acid prefix [anoate]

Question 8

Making esters questions-

Why was concentrated sulfuric acid added to the mixture

Answer 8

To act as a catalyst for the reaction

Remember must be concentrated

Question 9

Making esters questions-

Why was hot water bath used rather than Bunsen burner

Answer 9

The ester is very flammable so if a Bunsen burner is used it will catch fire

Question 10

Making esters questions-

Why was wet paper towel wrapped around test tube

Answer 10

To act as condensation agent

Question 11

Breaking esters reaction

Answer 11

Hydrolysis reaction

When a large molecule is split into two smaller molecules by reaction with a very small reaction like water