fermentation aim: to recall the chemistry of fermentation to understand that ethanol can be used as...
TRANSCRIPT
Fermentation
Aim:
To recall the chemistry of fermentation
To understand that ethanol can be used as a biofuel
Absinthe – from herbs including artemisia absinthium
Alcohol content
Beer 5%
Table Wine 8 – 14%
Sparkling wine 8 – 12%
Fortified wine (port, sherry) 17 –22%
Spirits:
vodka, gin, whiskey, brandy 37.5 – 40%
tequila
Every year 1000 young adults aged under 15 are admitted to hospital each year with acute alcohol poisoning. Large amounts of alcohol drunk quickly on just ONE occasion can KILL.
Grapes and grains contain carbohydrates
Starch
or
Sugar
These ferment to give
ethanol and carbon dioxide
Fermentation
Lime water
Yeast + glucose + water at 37oC
Glucose ethanol + carbon dioxideyeast
C6H12O6 2C2H5OH + 2CO2
Copy into your notes
Fractional Distillation
Ethanol is extracted from an ethanol/water mixture by distillation.
The mixture is heated to boiling and the ethanol boils first at 78oC.
Draw the apparatus
Biofuels
The ethanol produced by fermenting plant material (biomass) may be used as a fuel.
http://www.bbc.co.uk/radio4/science/rams/costingtheearth.ram