Topic 9- Part 4 (Alcohols and Carboxylic Acids) Flashcards
What is the functional group of acids?
OH
What is the chemical formula for Ethanol?
C₂H₅OH
What type of series is alcohol?
Homologous series
Are the first four alcohols (Methanol, Ethanol, Propanol and Butanol) soluable?
Yes
Are the first four alcohols (Methanol, Ethanol, Propanol and Butanol) Flammable?
Yes
Is alcohol acidic?
No, neutral
What happens when you oxidise an alcohol?
Carboxylic acid is produced
What happens when you combust an alcohol?
- Produces CO₂ and H₂O
What is the ending of carboxylic acid?
oic acid
Ethanoic acid
Butanoic acid
Alcohol uses and why?
Fuel- they can fully combust
Solvents- can dissolve things water cannot e.g lipids + hydrocarbons
What is the function group of carboxylic acids?
COOH
What is the chemical formula for Ethanoic Acid?
CH₃COOH
How strong are carboxylic acids?
-Weak
- Only one H+ ion is dissolved
- CH₃COOH ⇌ CH₃COO- + H+
What product is formed when carboxylic acids ionise in water?
Ignore water
Carboxylic acid ⇌…oate ione + Hydrogen
Word equation for ionising ethanoic acid
Ethanoic acid ⇌ Ethanoate + Hydrogen
Carboxylic acid + Metal Carbonate
Salt + Water + Carbon dioxide
acid + metal carbonate
How to make a carboxylic acid?
- Oxidising agent (gains electrons and looses an oxygen)
- Oxidise an alcohol
What is the functional group of an Ester and where is this group in the molecule ?
COO
in the middle
What is a distinctive property of Ester?
- Pleasent smell—> sweet/fruity
- Volatile —–> evaporate easily
used in perfumes and food flavourings
How is an Ester produced?
Alcohol + Carboxylic acid
Alcohol + Carboxylic acid ->
Ester + Water
Alcohol looses H and Carboxylic acid looses OH
Forms H₂O
What is used to speed up the reaction for an Ether?
Acid catalyst e.g Sulfuric acid
What is another name for an Ester group?
Ester link
Core Practical: Investigate the temperature rise produced in a
known mass of water by the combustion of the alcohols
ethanol, propanol, butanol and pentanol
- 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
How to get more precise results when burning alcohols to raise water temperatur?
- Mix water (avoid cold and hot spots)
- Use same setup for each alcohol —-> same distance from flame to conicle flask
- Insulate? add lid?
How is ethanol produced by fermentation?
Using yeast?
- Yeast catalyst breaks down glucose
-C₆H₁₂O₆ —> 2C₂H₅OH + 2CO₂
CARBON DIOXIDE AS BYPODUCT
What environment does fermentation have to occur in to produce alchohol?
- Anerobic (no oxygen)
