Ethanol Flashcards
what is fermentation?
Fermentation is the conversion of carbohydrates to alcohols or organic acids using yeast or bacteria in the absence of air.
how are spirits made ?
by fractional distillation of the fermentation mixture when it reaches a suitable aloholic content
In the distillation of fermented liquor to make rum, some producers work in batches.
Heat is applied directly to the pot still and the alcohol and aroma compounds giving the characteristic flavours evaporate.
uses of ethanol
Fuel- Ethanol containing 4.9% water is produced by distillation to be used for vehicles that run on ethanol only.
Alcoholic beverages
In the chemical industry to make halogenoalkanes, esters, ethers, ethanoic acid, and amines.
As an industrial solvent in paints and adhesives
As a solvent in the perfume industry
As an antiseptic
As an antidote to poisoning by other alcohols
effects of ethanol on the body
Ethanol is classed as a psychoactive drug- acts on the nervous system.
Results in changes in mood and how we view things.
If the amount of alcohol in the bloodstream increases, the short term effects are:
BAC 0.5- feeling of relaxation, increased talkativeness, impaired judgement
BAC 1.0- difficulty moving properly,giddiness, nausea, vomiting, symptoms of intoxication (blurred speech, aggressive behaviour)
BAC 3.0- loss of consciousness
At blood alcohol concentrations >1.0, ethanol acts as a depressant → lowers activity of particular parts of the brain
At blood alcohol concentrations >1.4, ethanol decreases flow of blood to the brain → loss of consciousness
Death can occur at concentrations >4.0
A buildup of alcohol in the body can result in liver cancer
Excessive alcohol consumption in pregnant women can result in foetal alcohol syndrome
social and economic impact of alcohol
Social consequences for individuals injured or families of those killed as a result of impaired judgement
Long term isolation
More treatment in hospitals required
Many working hours are lost when people do not turn up to work due to a hangover → decreases productivity
ethanol production and the environment
Conserves the diminishing supply of crude oil
Process is ‘carbon neutral’ even though when ethanol burns, carbon dioxide is returned to the atmosphere (the processes are in balance)
Cheaper and better for the environment than extracting petroleum from the ground and fractionally distilling it (still produces CO2 though)
Produces GHG when combusted from car engines but it is less than gasoline
Produces twice as much methanal and ethanal during the combustion from car engines → forms photochemical smog
Food production might decrease or get more expensive if crops are being used to make biofuels
Process of fermentation
Carbohydrate material is cut up into small pieces.
Malt extract is then added. Malt contains the enzyme, diastase. This enzyme catalyzes the conversion of the starch to a complex sugar.
2(C6H10O5)n + nH2O → C12H22O11
Yeast is then added. Yeast contains 2 enzymes: maltase and zymase.
The enzyme, maltase, catalyzes the conversion of the complex sugar to a simple sugar.
C12H22O11 + H2O → C6H12O6
The other enzyme, zymase, then catalyzes the conversion of the simple sugar to ethanol and carbon dioxide at 25oC.
C6H12O6 → 2C2H5OH + 2CO2
advantages of ethanol as a fuel
→ Less pollutants (no black smoke produced)
→ Renewable
→ Reduces petroleum imports
→ Conserves the world’s supply of crude oil
short term effects of alcohol
Initial relaxation
Loss of inhibitions
Impaired coordination
Slowing down of reflexes
Attitude changes
long term effects of alcohol
Cirrhosis of the liver
Damage to the pancreas
Damage to the heart
Neglect of self and family
Loss of job
Unable to take care of family
