Fermentation & Alcohols (Uses + Properties + Reactions)

What functional group do alcohols contain?

-OH

What are the first four alcohols?

Methanol — CH₃OH -- Ethanol — C₂H₅OH -- Propanol — C₃H₇OH -- Butanol — C₄H₉OH

How can you recognise an alcohol from its name?

Its name usually ends in -ol.

What happens when alcohols burn in air?

They undergo combustion, producing carbon dioxide and water during complete combustion.

What happens when alcohols react with sodium?

They react to produce hydrogen gas and a sodium alkoxide.

What happens when the first four alcohols are added to water?

They dissolve in water to form neutral solutions.

What happens when alcohols react with an oxidising agent?

They are oxidised to form carboxylic acids.

What happens to ethanol when it is oxidised?

Ethanol is oxidised to ethanoic acid.

Give common uses of the first four alcohols.

They can be used as fuels and solvents, and ethanol is also used in alcoholic drinks.

How can ethanol be produced biologically?

By fermentation of sugar solutions using yeast.

What conditions are required for fermentation?

Yeast -- A sugar solution -- Warm conditions -- Absence of oxygen / anaerobic conditions

What happens during fermentation?

glucose --> ethanol + carbon dioxide.

Why should fermentation not be too hot?

High temperatures can denature enzymes in the yeast, reducing/stopping fermentation.

Why are anaerobic conditions required?

In the absence of oxygen, yeast carries out anaerobic respiration/fermentation, producing ethanol.