burn in air very well in a combustion
reaction (release CO2 and H2O)
react with sodium to produce hydrogen
dissolve in water to form a neutral solution
methanol ( CH3OH)
contain the functional group - OH
homologus series - family of compounds with
the same general formula and have similar
chemical properties
ethanol ( CH3CH2OH)
( by oxidising agents or microbes)oxidised
ethanol becomes ethanoic acid (vinegar)
ethanol is harmful....in small amounts
cause drunkness....large amounts can be
toxic and cause death
carbon neutral
propanol (CH3CH2CH2OH)
Carboxylic acid
functional group is - COOH
Esters
functional group - COO
methyl methanoate ( HCOOCH3)
methyl ethanoate( CH3COOCH3
ethyl propanoate( CH3CH2COOCH2CH3
can be made by the reaction of alcohold and carboxylic
acids. reaction is slow an so is carried out in the prsence of
a concentrated acid like sulfuric acid which acts as a catylst
responsible for smells and flavours
of many fruits...esters can either be
extracted from fruits or made
artifically from alcohois and
carboxylic acids
also can be used as flavourings in foods
volatile liquids---- meaning low boiling points and readily
evaporate so they can reach scent receptors in your nose.
also smell pleasant so often used as purfumes
methanoic acid ( HCOOH)
ethanoic acid ( CH3COOH )
propanoic acid ( CHCCH2COOH )
dissolve in water to produce acidic solutions
react with carbonates to produce CO2 eg ethanoic acid
+ sodium carbonate = sodium ethanoate + water +
carbon dioxide
react with alcohols ( and acid catalyst) to make esters
do not ionise completely in water - weak acids
aqueous solutions have a higher pH than aqueous solutions
of strong acids with the same concentration
Vinegar and aspirin
butanoic acid - smell of rancid butter
and present in human sweat and
methanoic acid is found in ant stings