IC3.30.3 Homologous series
Homologous series
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IC3.30.3 Homologous series
Everyone smells slightly different because of the mix of
compounds in their sweat. Dogs are better than humans at
detecting these differences in sweat.
© Oxford University Press 2011
IC3.30.3 Homologous series
The compounds that give sweat its smell are
carboxylic acids. The carboxylic acids make up
a homologous series.
The series includes:
 methanoic acid
 ethanoic acid
 propanoic acid.
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IC3.30.3 Homologous series
All carboxylic acid molecules have the functional group –COOH,
in which the atoms are arranged like this:
© Oxford University Press 2011
IC3.30.3 Homologous series
As you go up any homologous series, there is a
gradual change in some properties, such as boiling
point and density.
© Oxford University Press 2011
IC3.30.3 Homologous series
1.
Describe the trends in density and boiling point
from methanoic acid to propanoic acid.
Density decreases and boiling points increase
down the homologous series.
© Oxford University Press 2011
IC3.30.3 Homologous series
2. What is the name of the homologous series that has
this functional group?
the carboxylic acids
© Oxford University Press 2011