Paper 2- Alcohols and ethanol

Question 1

What can alcohols be oxidised to form

Answer 1

carboxylic acids

Question 2

what does it mean when something is oxidised

Answer 2

when something is oxidised it gains electrons

Question 3

What does microbial oxidation form

Answer 3

carboxylic acids

Question 4

How are alcohols oxidised through the process of microbial oxidation

Answer 4

-microorganisms use oxygen in air to oxidise alcohols so they can use alcohols as an energy source

Question 5

What do alcohols undergo when they are burnt in enough oxygen

Answer 5

they undergo complete combustion

Question 6

give the word equation for the oxidation of ethanol when it is burnt

Answer 6

ethanol + oxygen –> carbon dioxide + water

Question 7

what is ethene produced from

Answer 7

crude oil

Question 8

name the 3 ways ethanol can be oxidised

Answer 8

burning in air or oxygen (complete combustion)

reaction with oxygen in the air to form ethanoic acid
(microbial oxidation)

heating with potassium dichromate(VI) in dilute sulfuric acid to form
ethanoic acid

Question 9

name the 2 ways ethanol can be manufactured by

Answer 9

reacting ethene with steam in the presence of a phosphoric acid catalyst
at a temperature of about 300 ºC and a pressure of about 60–70 atm

• the fermentation of glucose, in the absence of air, at an optimum
temperature of about 30 ºC and using the enzymes in yeast

Question 10

2 advantages of the production of ethanol using ethene and steam

Answer 10

• cheap process at the moment as ethene = cheap and not much is wasted
• however crude oil = non-renewable resource- so will start running out soon- soon using ethene to make ethanol will become very expensive

Question 11

what do carboxylic acids in aqueous solution react with metal carbonates to form

Answer 11

• salt
• water
• carbon dioxide

Question 12

carboxylic acids;

ethanoic acid + sodium carbonate –>

Answer 12

sodium ethanoate + water + carbon dioxide

Question 13

what do carboxylic acids react with metals to form

Answer 13

• salt

- hydrogen

Question 14

carboxylic acids;

ethanoic acid + magnesium –>

Answer 14

magnesium ethanoate + hydrogen

Question 15

what are esters formed from

Answer 15

alcohols and carboxylic acids

Question 16

Give the steps of how you would make ethyl ethanoate in a lab

Answer 16

1) add few drops of concentrated sulfuric acid to boiling tube using a dropping pipette
2) add 10 drops of ethanoic acid
3) add equal volume of ethanol
4) place boiling tube in beaker of weaker and place on tripod
5) heat using bunsen burner until water starts to boil and then turn off bunsen
6) after 1 minute, remove tube and allow it to cool
7) once cool pour mixture into test tube of sodium carbonate solution and mix
- layer of ester should form on top of solution