Transcript IC3.29.4 Reactions of alcohols

IC3.29.4 Reactions of alcohols
Reactions of alcohols
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
Alcohols react with sodium. The products are a salt and hydrogen.
For example:
ethanol + sodium  sodium ethoxide + hydrogen
2CH3CH2OH(l) + 2Na(s)  2CH3CH2ONa(aq) + H2(g)
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
Water reacts with sodium more
vigorously, but makes similar products:
sodium
water + sodium 
+ hydrogen
hydroxide
2H2O(l) + 2Na(s)  2NaOH(aq) + H2(g)
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
 The reactions of sodium with ethanol and with water
are similar because both water and ethanol contain
an –OH group.
 During the reaction, O–H bonds break.
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
An opened bottle of wine tastes
sour after a few days. The sour
taste comes from ethanoic acid.
Ethanoic acid forms when
oxygen from the air oxidises
some of the ethanol in the wine.
Ethanoic acid is the main acid
in vinegar.
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
You can also oxidise ethanol by
 the action of microbes
 reacting it with a chemical oxidising agent.
The chemical used in this photo oxidises ethanol to ethanoic acid.
The colour changes from orange to green in the process.
© Oxford University Press 2011
IC3.29.4 Reactions of alcohols
1. Name the salt formed when propanol reacts with
sodium.
sodium propoxide
2. Give two ways by which ethanol can be oxidised to
ethanoic acid.
Any two of:
 exposure to the air
 the action of microbes
 reacting with a chemical oxidising agent
© Oxford University Press 2011