Lesson 5: Alcohols

Question 1

What functional group do alcohols contain?

Answer 1

—OH

Question 2

What are the first four members of the homologous series of alcohols?

Answer 2

• Methanol.
• Ethanol.
• Propanol.
• Butanol.

Question 3

What is the solubility of alcohols in water like?

Answer 3

• Alcohols are soluble in water and form NEUTRAL SOLUTIONS.
• As the number of carbon atoms, in the alcohol increases, the solubility decreases.

Question 4

How do alcohols react with sodium?

Answer 4

Alcohol + sodium —> sodium prefix-oxide+ hydrogen
Ie. methanol + sodium –> sodium methoxide + hydogrogen (bubbles will be seen.)

Question 5

What are the products when alcohols react with oxidising agents?

Answer 5

Alcohol —> (oxidisng agent on top of arrow!!) Carboxylic acid + water

Question 6

Give an example of an oxidising agent that would react with an alcohol to form a carboxylic acid and water.

Answer 6

• acidified potassium dichromate.

Question 7

What are the products when alcohols are burnt in air?

Answer 7

Alcohol + oxygen –> carbon dioxide + water
ENERGY is released by this combustion reaction!

Question 8

Give 3 uses of alcohols.

Answer 8

1.) Fuels
2.) Solvents
3.) Alcoholic drinks (ethanol used in alcoholic drinks.)

Question 9

What is the word equation for fermentation?

Answer 9

glucose (any sugar solution) —> (yeast/ 30 degrees above the arrow) ethanol + carbon dioxide.

Question 10

What is produced when sugar solutions are fermented using yeast?

Answer 10

• Aqueous solutions of ethanol (in other words, ethanol + water.)

Question 11

What are the conditions required for fermentation of sugar ie. glucose using yeast?

2 conditions!!

Answer 11

• Temperature should be around 30 degrees celcius.
• Reaction must take place in anaerobic conditions (without oxygen.)