Alcohols

Question 1

Alcohols functional group

Answer 1

-OH

Question 2

Alcohols general formula

Answer 2

C(n)H(2n+2)O

Question 3

Methanol

Answer 3

General formula - CH3OH
Molecular formula - CH4O
Structural formula - CH3OH

Question 4

Ethanol

Answer 4

General formula - C2H5OH
Molecular formula - C2H6O
Structural formula - CH3CH2OH

Question 5

Propanol

Answer 5

General formula - C3H7OH
Molecular formula - C3H8O
Structural formula - CH3CH2CH2OH

Question 6

Butanol

Answer 6

General formula - C4H10OH
Molecular formula - C4H8O2
Structural formula - CH3CH2CH2CH2OH

Question 7

Uses of alcohols

Answer 7

-biofuels (methanol, ethanol)
-cleaning, mouthwash (can dissolve oily substances)
-alcoholic drinks (glucose + yeast —> ethanol + carbon dioxide)

Question 8

Combustion of alcohols

Answer 8

Alcohol + oxygen —> carbon dioxide + water
eg) C2H5OH + 3O2 —> 2CO2 + 3H2O

Question 9

Combustion of alcohols core practical

Answer 9

1) measure the initial mass of the alcohol burner containing alcohol
2) place the alcohol burner on a heat proof mat
3) use a measuring cylinder to add 100cm^3 of cold water to a conical flask and place the flask above the alcohol burner with a clamp
4) measure the initial temperature of the water
5) light the burner and wait a specific amount of time
6) record the final temperature of the water and the mass of the alcohol burner containing alcohol
7) calculate the change in temperature and mass and repeat

Question 10

Oxidation of alcohols

Answer 10

Alcohol + oxidising agent —> carboxylic acid + water
eg) CH3CH2OH + [O] —> CH3COOH + H2O