Alcohols Flashcards
What is the functional group of alcohols?
-OH
What is the general formula for an alcohol?
C(n)H(2n+1) OH
What process converts sugars like glucose into alcohols and carbon dioxide ?
Fermentation
What is the symbolic equation for the fermentation of glucose?
C6H12O6 -> 2 C2H5OH +2 CO2
That acts as a catalyst for the fermentation process?
Yeast
Why must fermentation take place at 35 degrees?
As the yeast breaks down at high temperatures
What is the name for the process of making ethanol not by fermentation?
Direct hydration
What is the word equation for the hydration reaction?
Ethene + steam -> Ethanol
What is the catalyst for the hydration of ethene?
Phosphoric acid
Which is the faster reaction for producing ethanol?
Hydration
What are two advantages of using hydration?
Its faster and produces pure ethanol
What is a problem with the ethanol produced by fermentation?
Its not pure
What is the raw material for hydration and where does it come from?
Ethene from oil
What happens when ethanol is heated to 180 degrees with phosphoric or sulfuric acid?
It is dehydrated to form ethene and water
What are the reactants for hydration?
Ethene and steam
What type of process is hydration?
Continuous
What type of process is fermentation ?
Batch
Why is ethanol from fermentation considered a biofuel?
It is produced from biomass
What is a primary alcohol?
When the carbon the OH group is attached to is connected to one other carbon
What is formed when primary alcohols are oxidised?
An aldehyde and water
How is ethanoic acid formed?
By oxidising ethanal
What must be oxidised to form ketones?
Secondary alcohols
What does this show?
RCHO + [O] -> RCOOH
An aldehyde being oxidised to form a carboxylic acid
What does Tollens’ reagent contain and what happens when it reacts with an aldehyde?
[Ag(NH3)2] + ions
The aldehyde reduces the ion and forms a silver mirror on the walls of the test tube
What happens when Fehling’s solution is add to Solution A containing ethanal and solution B containing propanone?
Solution A - Forms a red precipitate which is copper (1) oxide
Solution B - No reaction
