5. Alcohols Flashcards
General formula for alcohols?
CnH₂n₊₁OH
Are alcohols saturated or unsaturated?
Saturated
What is the functional group in alcohols?
-OH
What can the H in the O-H bond in alcohols do, in terms of bonding?
It can hydrogen bond with other alcohol molecules and with water
What can alcohols hydrogen bond to?
Other alcohol molecules and water
Why can alcohols form hydrogen bonds?
The H in the O-H bond
Why do alcohols have relatively high boiling points?
They can hydrogen bond
Why are many alcohols soluble in water?
They can hydrogen bond
What is it called when a molecule has a double bond and an O-H bond?
An alkenol
How can ethanol be manufactured industrially?
- hydration of alkenes
* fermentation to produce ethanol
What decides which method for ethanol to be manufactured?
Depends on desired purity of ethanol and the availability of the different raw materials in the country where is it made
What reaction takes place when alcohols are produced from alkenes?
Addition
Why does an addition reaction need to take place when alcohols are produced from alkenes?
To get rid of the double bond
What is the catalyst when alcohols are produced by hydration of alkenes?
Solid phosphoric acid catalyst (also possible with concentrated sulphuric acid)
What will be the purity of the ethanol produced by hydration of ethenes?
> 90%
What is the overall symbol equation for when ethanol is produced from ethene by hydration?
CH₂=CH₂ + H₂O ⇌ CH₃CH₂OH
What is the overall word equation for when ethanol is produced from ethene by hydration?
Ethene + Water ⇌ Ethanol
What are the conditions for the production of alcohol through hydration of alkenes?
- solid phosphoric acid catalyst
- 300°C
- 60atm
What of type pressures and temperatures are required for hydration of alkenes?
High temperatures and pressure (300°C and 60atm)
How are alcoholic drinks produced?
Fermentation of glucose
What happens during the fermentation of glucose to form alcohol?
- carbohydrates from plants are broken down into sugars (e.g. glucose)
- this is converted to ethanol and carbon dioxide
What is the fermentation of glucose catalysed by?
The action of enzymes (zymase) in yeast
What is the optimum temperature for zymase enzymes in yeast?
30-40°C
What is the overall symbol equation for the fermentation of glucose to produce ethanol?
C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂