Alcohols

Question 1

What is the general formula for alcohols?

Answer 1

C(n)H(2n+1)OH

Question 2

What is the functional group of alcohols?

Answer 2

-OH (hydroxyl)

Question 3

What are 4 smallest alcohols?

Answer 3

smalles to largest:
Methanol - CH(3)OH
Ethanol - C(2)H(5)OH
Propanol - C(3)H(7)OH
Butanol - C(4)H(9)OH

Question 4

How does the formula of the first 4 alcohols increase

Answer 4

An extra CH(2) is added with each increase

Question 5

What happens when alcohols react with an oxidising agent?

Answer 5

A carboxylic acid is produced

Question 6

What happen when alcohols react with sodium?

Answer 6

Hydrogen is produced

Question 7

What happens when alcohols react with water?

Answer 7

The alcohols dissolve to give a neutral solution

Question 8

What happens when alcohols react with air (and heat ofc)

Answer 8

Carbon dioxide and water is produced

Question 9

What is a carboxylic acid?

Answer 9

A carboxylic acid is an organic compound that contains a carboxyl group

Question 10

What is the functional group of carboxylic acids?

Answer 10

-(COOH) (carboxyl)

-C=O
I
Oh

Question 11

What is the general formula for carboxylic acids?

Answer 11

C(n)H(2n+1)COOH

Question 12

Are carboxylic acids strong or weak and how do we know this?

Answer 12

They are weak acids because they only partially ionise in water (not all the hydrogen atoms disassociate to form H+ ions)

Question 13

What happens when carboxylic acids react with carbonates?

Answer 13

They produce a SALT + CARBON DIOXIDE + WATER

Question 14

What happens when carboxylic acids react with water

Answer 14

They dissolve to give acidic solutions

Question 15

What happens when carboxylic acids react with alcohols?

Answer 15

They produce an ester and water:

E.g. ethanoic acid + ethanol → ethyl ethanoate + water

Question 16

What is produced when an alcohol is oxidised?

Answer 16

The carboxylic acid of that alcohol is produced (e.g when propanol is oxidised, propanoic acid is produced)

Question 17

What is fermentation?

Answer 17

The process of adding yeast to a sugar solution, this produces:

• An aqueous solution of ethanol
• Carbon dioxide

Question 18

What conditions are necessary for fermentation?

Answer 18

ideal conditions are:

• Temperature at around 37 degrees Celsius
• A slightly acidic solution
• Anaerobic condition (no oxygen)

Question 19

How can we extract the ethanol from the ethanol mixture we get from fermentation?

Answer 19

We can use fractional distillation to get the ethanol, this allows the producer to make a higher concentration of ethanol

Question 20

What is the general formula for carboxylic acids?

Answer 20

C(n-1)H(2n+1)COOH

Question 21

How do we know that alcohol react in a similar way to other alcohols

Answer 21

They are members of a homologous series and have the same functional group so we can predict how other molecules in that series will react

Question 22

What will we get when ethanolic acid is dissolved in water

Answer 22

Ethanolic acid is slightly ionising so it produces the ethanoate ion and H+