Topic 9- Part 4 (Alcohols and Carboxylic Acids)

Question 1

What is the functional group of acids?

Answer 1

OH

Question 2

What is the chemical formula for Ethanol?

Answer 2

C₂H₅OH

Question 3

What type of series is alcohol?

Answer 3

Homologous series

Question 4

Are the first four alcohols (Methanol, Ethanol, Propanol and Butanol) soluable?

Answer 4

Yes

Question 5

Are the first four alcohols (Methanol, Ethanol, Propanol and Butanol) Flammable?

Answer 5

Yes

Question 6

Is alcohol acidic?

Answer 6

No, neutral

Question 7

What happens when you oxidise an alcohol?

Answer 7

Carboxylic acid is produced

Question 8

What happens when you combust an alcohol?

Answer 8

• Produces CO₂ and H₂O

Question 9

What is the ending of carboxylic acid?

Answer 9

oic acid
Ethanoic acid
Butanoic acid

Question 10

Alcohol uses and why?

Answer 10

Fuel- they can fully combust
Solvents- can dissolve things water cannot e.g lipids + hydrocarbons

Question 11

What is the function group of carboxylic acids?

Answer 11

COOH

Question 12

What is the chemical formula for Ethanoic Acid?

Answer 12

CH₃COOH

Question 13

How strong are carboxylic acids?

Answer 13

-Weak
- Only one H+ ion is dissolved
- CH₃COOH ⇌ CH₃COO- + H+

Question 14

What product is formed when carboxylic acids ionise in water?

Ignore water

Answer 14

Carboxylic acid ⇌…oate ione + Hydrogen

Question 15

Word equation for ionising ethanoic acid

Answer 15

Ethanoic acid ⇌ Ethanoate + Hydrogen

Question 16

Carboxylic acid + Metal Carbonate

Answer 16

Salt + Water + Carbon dioxide

acid + metal carbonate

Question 17

How to make a carboxylic acid?

Answer 17

• Oxidising agent (gains electrons and looses an oxygen)
• Oxidise an alcohol

Question 18

What is the functional group of an Ester and where is this group in the molecule ?

Answer 18

COO
in the middle

Question 19

What is a distinctive property of Ester?

Answer 19

• Pleasent smell—> sweet/fruity
• Volatile —–> evaporate easily

used in perfumes and food flavourings

Question 20

How is an Ester produced?

Answer 20

Alcohol + Carboxylic acid

Question 21

Alcohol + Carboxylic acid ->

Answer 21

Ester + Water

Alcohol looses H and Carboxylic acid looses OH

Forms H₂O

Question 22

What is used to speed up the reaction for an Ether?

Answer 22

Acid catalyst e.g Sulfuric acid

Question 23

What is another name for an Ester group?

Answer 23

Ester link

Question 24

Core Practical: Investigate the temperature rise produced in a
known mass of water by the combustion of the alcohols
ethanol, propanol, butanol and pentanol

Answer 24

• Find mass of … spirit burner
• Light the spirit burner
• Heat water by 20 degrees
• Take readings of new mass of spirit burner
  ——> It takes … of … spirit to raise 100cm^3 of water
  repeat with other spirits

Question 25

How to get more precise results when burning alcohols to raise water temperatur?

Answer 25

• Mix water (avoid cold and hot spots)
• Use same setup for each alcohol —-> same distance from flame to conicle flask
• Insulate? add lid?

Question 26

How is ethanol produced by fermentation?

Using yeast?

Answer 26

• Yeast catalyst breaks down glucose
  -C₆H₁₂O₆ —> 2C₂H₅OH + 2CO₂

CARBON DIOXIDE AS BYPODUCT

Question 27

What environment does fermentation have to occur in to produce alchohol?

Answer 27

• Anerobic (no oxygen)