Production of Ethanol Flashcards
What is ethanol?
Ethanol is an alcohol with 2 carbon atoms. Its formula is C2H5OH.
Give 4 uses of ethanol.
- Chemical feedstock to produce other chemicals.
- As a solvent.
- Fuel (when it’s made by living organisms it’s called a biofuel).
- Making alcoholic drinks.
How is ethanol made from ethene?
Ethene is reacted with steam (gaseous water) at a high temperature, high pressure, and with a phosphoric acid catalyst.
What is the word equation for the reaction of making ethanol from ethene?
ethene + water ➔ ethanol
What are the pros and cons of making ethanol from ethene?
Pros: Ethene is cheap and the reaction itself is cheap and efficient.
Cons: Ethene is made from crude oil which is a non-renewable resource.
What does the term ‘fermentation’ mean with reference to ethanol?
Fermentation is the anaerobic respiration of sugars by yeast cells to produce ethanol and carbon dioxide.
What is the word equation for the reaction of making ethanol by fermentation?
glucose ➔ ethanol + carbon dioxide
What are the conditions for fermentation?
- Yeast.
- Glucose for the yeast to respire.
- 30-40 degrees celsius.
- Anaerobic conditions (no oxygen).
What are the pros and cons of making ethanol by fermentation?
Pros: Glucose used is a renewable resource so can’t run out. Yeast are easy to grow.
Cons: The process can be relatively slow. The ethanol produced isn’t pure, so must be distilled by fractional distillation.
Why are temperatures of 30-40 °C used when making ethanol by fermentation?
The reaction is catalysed by enzymes, and 30-40°C is the optimum temperature for them to function.
